1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 37 */ 38 39 /* 40 * External virtual filesystem routines 41 */ 42 43 #include <sys/cdefs.h> 44 __FBSDID("$FreeBSD$"); 45 46 #include "opt_compat.h" 47 #include "opt_ddb.h" 48 #include "opt_watchdog.h" 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/bio.h> 53 #include <sys/buf.h> 54 #include <sys/condvar.h> 55 #include <sys/conf.h> 56 #include <sys/counter.h> 57 #include <sys/dirent.h> 58 #include <sys/event.h> 59 #include <sys/eventhandler.h> 60 #include <sys/extattr.h> 61 #include <sys/file.h> 62 #include <sys/fcntl.h> 63 #include <sys/jail.h> 64 #include <sys/kdb.h> 65 #include <sys/kernel.h> 66 #include <sys/kthread.h> 67 #include <sys/lockf.h> 68 #include <sys/malloc.h> 69 #include <sys/mount.h> 70 #include <sys/namei.h> 71 #include <sys/pctrie.h> 72 #include <sys/priv.h> 73 #include <sys/reboot.h> 74 #include <sys/refcount.h> 75 #include <sys/rwlock.h> 76 #include <sys/sched.h> 77 #include <sys/sleepqueue.h> 78 #include <sys/smp.h> 79 #include <sys/stat.h> 80 #include <sys/sysctl.h> 81 #include <sys/syslog.h> 82 #include <sys/vmmeter.h> 83 #include <sys/vnode.h> 84 #include <sys/watchdog.h> 85 86 #include <machine/stdarg.h> 87 88 #include <security/mac/mac_framework.h> 89 90 #include <vm/vm.h> 91 #include <vm/vm_object.h> 92 #include <vm/vm_extern.h> 93 #include <vm/pmap.h> 94 #include <vm/vm_map.h> 95 #include <vm/vm_page.h> 96 #include <vm/vm_kern.h> 97 #include <vm/uma.h> 98 99 #ifdef DDB 100 #include <ddb/ddb.h> 101 #endif 102 103 static void delmntque(struct vnode *vp); 104 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 105 int slpflag, int slptimeo); 106 static void syncer_shutdown(void *arg, int howto); 107 static int vtryrecycle(struct vnode *vp); 108 static void v_init_counters(struct vnode *); 109 static void v_incr_usecount(struct vnode *); 110 static void v_incr_usecount_locked(struct vnode *); 111 static void v_incr_devcount(struct vnode *); 112 static void v_decr_devcount(struct vnode *); 113 static void vgonel(struct vnode *); 114 static void vfs_knllock(void *arg); 115 static void vfs_knlunlock(void *arg); 116 static void vfs_knl_assert_locked(void *arg); 117 static void vfs_knl_assert_unlocked(void *arg); 118 static void vnlru_return_batches(struct vfsops *mnt_op); 119 static void destroy_vpollinfo(struct vpollinfo *vi); 120 121 /* 122 * Number of vnodes in existence. Increased whenever getnewvnode() 123 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 124 */ 125 static unsigned long numvnodes; 126 127 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 128 "Number of vnodes in existence"); 129 130 static counter_u64_t vnodes_created; 131 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created, 132 "Number of vnodes created by getnewvnode"); 133 134 static u_long mnt_free_list_batch = 128; 135 SYSCTL_ULONG(_vfs, OID_AUTO, mnt_free_list_batch, CTLFLAG_RW, 136 &mnt_free_list_batch, 0, "Limit of vnodes held on mnt's free list"); 137 138 /* 139 * Conversion tables for conversion from vnode types to inode formats 140 * and back. 141 */ 142 enum vtype iftovt_tab[16] = { 143 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 144 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 145 }; 146 int vttoif_tab[10] = { 147 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 148 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 149 }; 150 151 /* 152 * List of vnodes that are ready for recycling. 153 */ 154 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 155 156 /* 157 * "Free" vnode target. Free vnodes are rarely completely free, but are 158 * just ones that are cheap to recycle. Usually they are for files which 159 * have been stat'd but not read; these usually have inode and namecache 160 * data attached to them. This target is the preferred minimum size of a 161 * sub-cache consisting mostly of such files. The system balances the size 162 * of this sub-cache with its complement to try to prevent either from 163 * thrashing while the other is relatively inactive. The targets express 164 * a preference for the best balance. 165 * 166 * "Above" this target there are 2 further targets (watermarks) related 167 * to recyling of free vnodes. In the best-operating case, the cache is 168 * exactly full, the free list has size between vlowat and vhiwat above the 169 * free target, and recycling from it and normal use maintains this state. 170 * Sometimes the free list is below vlowat or even empty, but this state 171 * is even better for immediate use provided the cache is not full. 172 * Otherwise, vnlru_proc() runs to reclaim enough vnodes (usually non-free 173 * ones) to reach one of these states. The watermarks are currently hard- 174 * coded as 4% and 9% of the available space higher. These and the default 175 * of 25% for wantfreevnodes are too large if the memory size is large. 176 * E.g., 9% of 75% of MAXVNODES is more than 566000 vnodes to reclaim 177 * whenever vnlru_proc() becomes active. 178 */ 179 static u_long wantfreevnodes; 180 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, 181 &wantfreevnodes, 0, "Target for minimum number of \"free\" vnodes"); 182 static u_long freevnodes; 183 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, 184 &freevnodes, 0, "Number of \"free\" vnodes"); 185 186 static counter_u64_t recycles_count; 187 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count, 188 "Number of vnodes recycled to meet vnode cache targets"); 189 190 /* 191 * Various variables used for debugging the new implementation of 192 * reassignbuf(). 193 * XXX these are probably of (very) limited utility now. 194 */ 195 static int reassignbufcalls; 196 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 197 "Number of calls to reassignbuf"); 198 199 static counter_u64_t free_owe_inact; 200 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, free_owe_inact, CTLFLAG_RD, &free_owe_inact, 201 "Number of times free vnodes kept on active list due to VFS " 202 "owing inactivation"); 203 204 /* To keep more than one thread at a time from running vfs_getnewfsid */ 205 static struct mtx mntid_mtx; 206 207 /* 208 * Lock for any access to the following: 209 * vnode_free_list 210 * numvnodes 211 * freevnodes 212 */ 213 static struct mtx vnode_free_list_mtx; 214 215 /* Publicly exported FS */ 216 struct nfs_public nfs_pub; 217 218 static uma_zone_t buf_trie_zone; 219 220 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 221 static uma_zone_t vnode_zone; 222 static uma_zone_t vnodepoll_zone; 223 224 /* 225 * The workitem queue. 226 * 227 * It is useful to delay writes of file data and filesystem metadata 228 * for tens of seconds so that quickly created and deleted files need 229 * not waste disk bandwidth being created and removed. To realize this, 230 * we append vnodes to a "workitem" queue. When running with a soft 231 * updates implementation, most pending metadata dependencies should 232 * not wait for more than a few seconds. Thus, mounted on block devices 233 * are delayed only about a half the time that file data is delayed. 234 * Similarly, directory updates are more critical, so are only delayed 235 * about a third the time that file data is delayed. Thus, there are 236 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 237 * one each second (driven off the filesystem syncer process). The 238 * syncer_delayno variable indicates the next queue that is to be processed. 239 * Items that need to be processed soon are placed in this queue: 240 * 241 * syncer_workitem_pending[syncer_delayno] 242 * 243 * A delay of fifteen seconds is done by placing the request fifteen 244 * entries later in the queue: 245 * 246 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 247 * 248 */ 249 static int syncer_delayno; 250 static long syncer_mask; 251 LIST_HEAD(synclist, bufobj); 252 static struct synclist *syncer_workitem_pending; 253 /* 254 * The sync_mtx protects: 255 * bo->bo_synclist 256 * sync_vnode_count 257 * syncer_delayno 258 * syncer_state 259 * syncer_workitem_pending 260 * syncer_worklist_len 261 * rushjob 262 */ 263 static struct mtx sync_mtx; 264 static struct cv sync_wakeup; 265 266 #define SYNCER_MAXDELAY 32 267 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 268 static int syncdelay = 30; /* max time to delay syncing data */ 269 static int filedelay = 30; /* time to delay syncing files */ 270 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 271 "Time to delay syncing files (in seconds)"); 272 static int dirdelay = 29; /* time to delay syncing directories */ 273 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 274 "Time to delay syncing directories (in seconds)"); 275 static int metadelay = 28; /* time to delay syncing metadata */ 276 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 277 "Time to delay syncing metadata (in seconds)"); 278 static int rushjob; /* number of slots to run ASAP */ 279 static int stat_rush_requests; /* number of times I/O speeded up */ 280 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 281 "Number of times I/O speeded up (rush requests)"); 282 283 /* 284 * When shutting down the syncer, run it at four times normal speed. 285 */ 286 #define SYNCER_SHUTDOWN_SPEEDUP 4 287 static int sync_vnode_count; 288 static int syncer_worklist_len; 289 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 290 syncer_state; 291 292 /* Target for maximum number of vnodes. */ 293 int desiredvnodes; 294 static int gapvnodes; /* gap between wanted and desired */ 295 static int vhiwat; /* enough extras after expansion */ 296 static int vlowat; /* minimal extras before expansion */ 297 static int vstir; /* nonzero to stir non-free vnodes */ 298 static volatile int vsmalltrigger = 8; /* pref to keep if > this many pages */ 299 300 static int 301 sysctl_update_desiredvnodes(SYSCTL_HANDLER_ARGS) 302 { 303 int error, old_desiredvnodes; 304 305 old_desiredvnodes = desiredvnodes; 306 if ((error = sysctl_handle_int(oidp, arg1, arg2, req)) != 0) 307 return (error); 308 if (old_desiredvnodes != desiredvnodes) { 309 wantfreevnodes = desiredvnodes / 4; 310 /* XXX locking seems to be incomplete. */ 311 vfs_hash_changesize(desiredvnodes); 312 cache_changesize(desiredvnodes); 313 } 314 return (0); 315 } 316 317 SYSCTL_PROC(_kern, KERN_MAXVNODES, maxvnodes, 318 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, &desiredvnodes, 0, 319 sysctl_update_desiredvnodes, "I", "Target for maximum number of vnodes"); 320 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 321 &wantfreevnodes, 0, "Old name for vfs.wantfreevnodes (legacy)"); 322 static int vnlru_nowhere; 323 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 324 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 325 326 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 327 static int vnsz2log; 328 329 /* 330 * Support for the bufobj clean & dirty pctrie. 331 */ 332 static void * 333 buf_trie_alloc(struct pctrie *ptree) 334 { 335 336 return uma_zalloc(buf_trie_zone, M_NOWAIT); 337 } 338 339 static void 340 buf_trie_free(struct pctrie *ptree, void *node) 341 { 342 343 uma_zfree(buf_trie_zone, node); 344 } 345 PCTRIE_DEFINE(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free); 346 347 /* 348 * Initialize the vnode management data structures. 349 * 350 * Reevaluate the following cap on the number of vnodes after the physical 351 * memory size exceeds 512GB. In the limit, as the physical memory size 352 * grows, the ratio of the memory size in KB to vnodes approaches 64:1. 353 */ 354 #ifndef MAXVNODES_MAX 355 #define MAXVNODES_MAX (512 * 1024 * 1024 / 64) /* 8M */ 356 #endif 357 358 /* 359 * Initialize a vnode as it first enters the zone. 360 */ 361 static int 362 vnode_init(void *mem, int size, int flags) 363 { 364 struct vnode *vp; 365 366 vp = mem; 367 bzero(vp, size); 368 /* 369 * Setup locks. 370 */ 371 vp->v_vnlock = &vp->v_lock; 372 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 373 /* 374 * By default, don't allow shared locks unless filesystems opt-in. 375 */ 376 lockinit(vp->v_vnlock, PVFS, "vnode", VLKTIMEOUT, 377 LK_NOSHARE | LK_IS_VNODE); 378 /* 379 * Initialize bufobj. 380 */ 381 bufobj_init(&vp->v_bufobj, vp); 382 /* 383 * Initialize namecache. 384 */ 385 LIST_INIT(&vp->v_cache_src); 386 TAILQ_INIT(&vp->v_cache_dst); 387 /* 388 * Initialize rangelocks. 389 */ 390 rangelock_init(&vp->v_rl); 391 return (0); 392 } 393 394 /* 395 * Free a vnode when it is cleared from the zone. 396 */ 397 static void 398 vnode_fini(void *mem, int size) 399 { 400 struct vnode *vp; 401 struct bufobj *bo; 402 403 vp = mem; 404 rangelock_destroy(&vp->v_rl); 405 lockdestroy(vp->v_vnlock); 406 mtx_destroy(&vp->v_interlock); 407 bo = &vp->v_bufobj; 408 rw_destroy(BO_LOCKPTR(bo)); 409 } 410 411 /* 412 * Provide the size of NFS nclnode and NFS fh for calculation of the 413 * vnode memory consumption. The size is specified directly to 414 * eliminate dependency on NFS-private header. 415 * 416 * Other filesystems may use bigger or smaller (like UFS and ZFS) 417 * private inode data, but the NFS-based estimation is ample enough. 418 * Still, we care about differences in the size between 64- and 32-bit 419 * platforms. 420 * 421 * Namecache structure size is heuristically 422 * sizeof(struct namecache_ts) + CACHE_PATH_CUTOFF + 1. 423 */ 424 #ifdef _LP64 425 #define NFS_NCLNODE_SZ (528 + 64) 426 #define NC_SZ 148 427 #else 428 #define NFS_NCLNODE_SZ (360 + 32) 429 #define NC_SZ 92 430 #endif 431 432 static void 433 vntblinit(void *dummy __unused) 434 { 435 u_int i; 436 int physvnodes, virtvnodes; 437 438 /* 439 * Desiredvnodes is a function of the physical memory size and the 440 * kernel's heap size. Generally speaking, it scales with the 441 * physical memory size. The ratio of desiredvnodes to the physical 442 * memory size is 1:16 until desiredvnodes exceeds 98,304. 443 * Thereafter, the 444 * marginal ratio of desiredvnodes to the physical memory size is 445 * 1:64. However, desiredvnodes is limited by the kernel's heap 446 * size. The memory required by desiredvnodes vnodes and vm objects 447 * must not exceed 1/10th of the kernel's heap size. 448 */ 449 physvnodes = maxproc + pgtok(vm_cnt.v_page_count) / 64 + 450 3 * min(98304 * 16, pgtok(vm_cnt.v_page_count)) / 64; 451 virtvnodes = vm_kmem_size / (10 * (sizeof(struct vm_object) + 452 sizeof(struct vnode) + NC_SZ * ncsizefactor + NFS_NCLNODE_SZ)); 453 desiredvnodes = min(physvnodes, virtvnodes); 454 if (desiredvnodes > MAXVNODES_MAX) { 455 if (bootverbose) 456 printf("Reducing kern.maxvnodes %d -> %d\n", 457 desiredvnodes, MAXVNODES_MAX); 458 desiredvnodes = MAXVNODES_MAX; 459 } 460 wantfreevnodes = desiredvnodes / 4; 461 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 462 TAILQ_INIT(&vnode_free_list); 463 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 464 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 465 vnode_init, vnode_fini, UMA_ALIGN_PTR, 0); 466 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 467 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 468 /* 469 * Preallocate enough nodes to support one-per buf so that 470 * we can not fail an insert. reassignbuf() callers can not 471 * tolerate the insertion failure. 472 */ 473 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(), 474 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR, 475 UMA_ZONE_NOFREE | UMA_ZONE_VM); 476 uma_prealloc(buf_trie_zone, nbuf); 477 478 vnodes_created = counter_u64_alloc(M_WAITOK); 479 recycles_count = counter_u64_alloc(M_WAITOK); 480 free_owe_inact = counter_u64_alloc(M_WAITOK); 481 482 /* 483 * Initialize the filesystem syncer. 484 */ 485 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 486 &syncer_mask); 487 syncer_maxdelay = syncer_mask + 1; 488 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 489 cv_init(&sync_wakeup, "syncer"); 490 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 491 vnsz2log++; 492 vnsz2log--; 493 } 494 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 495 496 497 /* 498 * Mark a mount point as busy. Used to synchronize access and to delay 499 * unmounting. Eventually, mountlist_mtx is not released on failure. 500 * 501 * vfs_busy() is a custom lock, it can block the caller. 502 * vfs_busy() only sleeps if the unmount is active on the mount point. 503 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 504 * vnode belonging to mp. 505 * 506 * Lookup uses vfs_busy() to traverse mount points. 507 * root fs var fs 508 * / vnode lock A / vnode lock (/var) D 509 * /var vnode lock B /log vnode lock(/var/log) E 510 * vfs_busy lock C vfs_busy lock F 511 * 512 * Within each file system, the lock order is C->A->B and F->D->E. 513 * 514 * When traversing across mounts, the system follows that lock order: 515 * 516 * C->A->B 517 * | 518 * +->F->D->E 519 * 520 * The lookup() process for namei("/var") illustrates the process: 521 * VOP_LOOKUP() obtains B while A is held 522 * vfs_busy() obtains a shared lock on F while A and B are held 523 * vput() releases lock on B 524 * vput() releases lock on A 525 * VFS_ROOT() obtains lock on D while shared lock on F is held 526 * vfs_unbusy() releases shared lock on F 527 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 528 * Attempt to lock A (instead of vp_crossmp) while D is held would 529 * violate the global order, causing deadlocks. 530 * 531 * dounmount() locks B while F is drained. 532 */ 533 int 534 vfs_busy(struct mount *mp, int flags) 535 { 536 537 MPASS((flags & ~MBF_MASK) == 0); 538 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 539 540 MNT_ILOCK(mp); 541 MNT_REF(mp); 542 /* 543 * If mount point is currently being unmounted, sleep until the 544 * mount point fate is decided. If thread doing the unmounting fails, 545 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 546 * that this mount point has survived the unmount attempt and vfs_busy 547 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 548 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 549 * about to be really destroyed. vfs_busy needs to release its 550 * reference on the mount point in this case and return with ENOENT, 551 * telling the caller that mount mount it tried to busy is no longer 552 * valid. 553 */ 554 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 555 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 556 MNT_REL(mp); 557 MNT_IUNLOCK(mp); 558 CTR1(KTR_VFS, "%s: failed busying before sleeping", 559 __func__); 560 return (ENOENT); 561 } 562 if (flags & MBF_MNTLSTLOCK) 563 mtx_unlock(&mountlist_mtx); 564 mp->mnt_kern_flag |= MNTK_MWAIT; 565 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 566 if (flags & MBF_MNTLSTLOCK) 567 mtx_lock(&mountlist_mtx); 568 MNT_ILOCK(mp); 569 } 570 if (flags & MBF_MNTLSTLOCK) 571 mtx_unlock(&mountlist_mtx); 572 mp->mnt_lockref++; 573 MNT_IUNLOCK(mp); 574 return (0); 575 } 576 577 /* 578 * Free a busy filesystem. 579 */ 580 void 581 vfs_unbusy(struct mount *mp) 582 { 583 584 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 585 MNT_ILOCK(mp); 586 MNT_REL(mp); 587 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 588 mp->mnt_lockref--; 589 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 590 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 591 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 592 mp->mnt_kern_flag &= ~MNTK_DRAINING; 593 wakeup(&mp->mnt_lockref); 594 } 595 MNT_IUNLOCK(mp); 596 } 597 598 /* 599 * Lookup a mount point by filesystem identifier. 600 */ 601 struct mount * 602 vfs_getvfs(fsid_t *fsid) 603 { 604 struct mount *mp; 605 606 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 607 mtx_lock(&mountlist_mtx); 608 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 609 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 610 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 611 vfs_ref(mp); 612 mtx_unlock(&mountlist_mtx); 613 return (mp); 614 } 615 } 616 mtx_unlock(&mountlist_mtx); 617 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 618 return ((struct mount *) 0); 619 } 620 621 /* 622 * Lookup a mount point by filesystem identifier, busying it before 623 * returning. 624 * 625 * To avoid congestion on mountlist_mtx, implement simple direct-mapped 626 * cache for popular filesystem identifiers. The cache is lockess, using 627 * the fact that struct mount's are never freed. In worst case we may 628 * get pointer to unmounted or even different filesystem, so we have to 629 * check what we got, and go slow way if so. 630 */ 631 struct mount * 632 vfs_busyfs(fsid_t *fsid) 633 { 634 #define FSID_CACHE_SIZE 256 635 typedef struct mount * volatile vmp_t; 636 static vmp_t cache[FSID_CACHE_SIZE]; 637 struct mount *mp; 638 int error; 639 uint32_t hash; 640 641 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 642 hash = fsid->val[0] ^ fsid->val[1]; 643 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1); 644 mp = cache[hash]; 645 if (mp == NULL || 646 mp->mnt_stat.f_fsid.val[0] != fsid->val[0] || 647 mp->mnt_stat.f_fsid.val[1] != fsid->val[1]) 648 goto slow; 649 if (vfs_busy(mp, 0) != 0) { 650 cache[hash] = NULL; 651 goto slow; 652 } 653 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 654 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) 655 return (mp); 656 else 657 vfs_unbusy(mp); 658 659 slow: 660 mtx_lock(&mountlist_mtx); 661 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 662 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 663 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 664 error = vfs_busy(mp, MBF_MNTLSTLOCK); 665 if (error) { 666 cache[hash] = NULL; 667 mtx_unlock(&mountlist_mtx); 668 return (NULL); 669 } 670 cache[hash] = mp; 671 return (mp); 672 } 673 } 674 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 675 mtx_unlock(&mountlist_mtx); 676 return ((struct mount *) 0); 677 } 678 679 /* 680 * Check if a user can access privileged mount options. 681 */ 682 int 683 vfs_suser(struct mount *mp, struct thread *td) 684 { 685 int error; 686 687 /* 688 * If the thread is jailed, but this is not a jail-friendly file 689 * system, deny immediately. 690 */ 691 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 692 return (EPERM); 693 694 /* 695 * If the file system was mounted outside the jail of the calling 696 * thread, deny immediately. 697 */ 698 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 699 return (EPERM); 700 701 /* 702 * If file system supports delegated administration, we don't check 703 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 704 * by the file system itself. 705 * If this is not the user that did original mount, we check for 706 * the PRIV_VFS_MOUNT_OWNER privilege. 707 */ 708 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 709 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 710 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 711 return (error); 712 } 713 return (0); 714 } 715 716 /* 717 * Get a new unique fsid. Try to make its val[0] unique, since this value 718 * will be used to create fake device numbers for stat(). Also try (but 719 * not so hard) make its val[0] unique mod 2^16, since some emulators only 720 * support 16-bit device numbers. We end up with unique val[0]'s for the 721 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 722 * 723 * Keep in mind that several mounts may be running in parallel. Starting 724 * the search one past where the previous search terminated is both a 725 * micro-optimization and a defense against returning the same fsid to 726 * different mounts. 727 */ 728 void 729 vfs_getnewfsid(struct mount *mp) 730 { 731 static uint16_t mntid_base; 732 struct mount *nmp; 733 fsid_t tfsid; 734 int mtype; 735 736 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 737 mtx_lock(&mntid_mtx); 738 mtype = mp->mnt_vfc->vfc_typenum; 739 tfsid.val[1] = mtype; 740 mtype = (mtype & 0xFF) << 24; 741 for (;;) { 742 tfsid.val[0] = makedev(255, 743 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 744 mntid_base++; 745 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 746 break; 747 vfs_rel(nmp); 748 } 749 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 750 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 751 mtx_unlock(&mntid_mtx); 752 } 753 754 /* 755 * Knob to control the precision of file timestamps: 756 * 757 * 0 = seconds only; nanoseconds zeroed. 758 * 1 = seconds and nanoseconds, accurate within 1/HZ. 759 * 2 = seconds and nanoseconds, truncated to microseconds. 760 * >=3 = seconds and nanoseconds, maximum precision. 761 */ 762 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 763 764 static int timestamp_precision = TSP_USEC; 765 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 766 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 767 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to us, " 768 "3+: sec + ns (max. precision))"); 769 770 /* 771 * Get a current timestamp. 772 */ 773 void 774 vfs_timestamp(struct timespec *tsp) 775 { 776 struct timeval tv; 777 778 switch (timestamp_precision) { 779 case TSP_SEC: 780 tsp->tv_sec = time_second; 781 tsp->tv_nsec = 0; 782 break; 783 case TSP_HZ: 784 getnanotime(tsp); 785 break; 786 case TSP_USEC: 787 microtime(&tv); 788 TIMEVAL_TO_TIMESPEC(&tv, tsp); 789 break; 790 case TSP_NSEC: 791 default: 792 nanotime(tsp); 793 break; 794 } 795 } 796 797 /* 798 * Set vnode attributes to VNOVAL 799 */ 800 void 801 vattr_null(struct vattr *vap) 802 { 803 804 vap->va_type = VNON; 805 vap->va_size = VNOVAL; 806 vap->va_bytes = VNOVAL; 807 vap->va_mode = VNOVAL; 808 vap->va_nlink = VNOVAL; 809 vap->va_uid = VNOVAL; 810 vap->va_gid = VNOVAL; 811 vap->va_fsid = VNOVAL; 812 vap->va_fileid = VNOVAL; 813 vap->va_blocksize = VNOVAL; 814 vap->va_rdev = VNOVAL; 815 vap->va_atime.tv_sec = VNOVAL; 816 vap->va_atime.tv_nsec = VNOVAL; 817 vap->va_mtime.tv_sec = VNOVAL; 818 vap->va_mtime.tv_nsec = VNOVAL; 819 vap->va_ctime.tv_sec = VNOVAL; 820 vap->va_ctime.tv_nsec = VNOVAL; 821 vap->va_birthtime.tv_sec = VNOVAL; 822 vap->va_birthtime.tv_nsec = VNOVAL; 823 vap->va_flags = VNOVAL; 824 vap->va_gen = VNOVAL; 825 vap->va_vaflags = 0; 826 } 827 828 /* 829 * This routine is called when we have too many vnodes. It attempts 830 * to free <count> vnodes and will potentially free vnodes that still 831 * have VM backing store (VM backing store is typically the cause 832 * of a vnode blowout so we want to do this). Therefore, this operation 833 * is not considered cheap. 834 * 835 * A number of conditions may prevent a vnode from being reclaimed. 836 * the buffer cache may have references on the vnode, a directory 837 * vnode may still have references due to the namei cache representing 838 * underlying files, or the vnode may be in active use. It is not 839 * desirable to reuse such vnodes. These conditions may cause the 840 * number of vnodes to reach some minimum value regardless of what 841 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 842 */ 843 static int 844 vlrureclaim(struct mount *mp, int reclaim_nc_src, int trigger) 845 { 846 struct vnode *vp; 847 int count, done, target; 848 849 done = 0; 850 vn_start_write(NULL, &mp, V_WAIT); 851 MNT_ILOCK(mp); 852 count = mp->mnt_nvnodelistsize; 853 target = count * (int64_t)gapvnodes / imax(desiredvnodes, 1); 854 target = target / 10 + 1; 855 while (count != 0 && done < target) { 856 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 857 while (vp != NULL && vp->v_type == VMARKER) 858 vp = TAILQ_NEXT(vp, v_nmntvnodes); 859 if (vp == NULL) 860 break; 861 /* 862 * XXX LRU is completely broken for non-free vnodes. First 863 * by calling here in mountpoint order, then by moving 864 * unselected vnodes to the end here, and most grossly by 865 * removing the vlruvp() function that was supposed to 866 * maintain the order. (This function was born broken 867 * since syncer problems prevented it doing anything.) The 868 * order is closer to LRC (C = Created). 869 * 870 * LRU reclaiming of vnodes seems to have last worked in 871 * FreeBSD-3 where LRU wasn't mentioned under any spelling. 872 * Then there was no hold count, and inactive vnodes were 873 * simply put on the free list in LRU order. The separate 874 * lists also break LRU. We prefer to reclaim from the 875 * free list for technical reasons. This tends to thrash 876 * the free list to keep very unrecently used held vnodes. 877 * The problem is mitigated by keeping the free list large. 878 */ 879 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 880 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 881 --count; 882 if (!VI_TRYLOCK(vp)) 883 goto next_iter; 884 /* 885 * If it's been deconstructed already, it's still 886 * referenced, or it exceeds the trigger, skip it. 887 * Also skip free vnodes. We are trying to make space 888 * to expand the free list, not reduce it. 889 */ 890 if (vp->v_usecount || 891 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)) || 892 ((vp->v_iflag & VI_FREE) != 0) || 893 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 894 vp->v_object->resident_page_count > trigger)) { 895 VI_UNLOCK(vp); 896 goto next_iter; 897 } 898 MNT_IUNLOCK(mp); 899 vholdl(vp); 900 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 901 vdrop(vp); 902 goto next_iter_mntunlocked; 903 } 904 VI_LOCK(vp); 905 /* 906 * v_usecount may have been bumped after VOP_LOCK() dropped 907 * the vnode interlock and before it was locked again. 908 * 909 * It is not necessary to recheck VI_DOOMED because it can 910 * only be set by another thread that holds both the vnode 911 * lock and vnode interlock. If another thread has the 912 * vnode lock before we get to VOP_LOCK() and obtains the 913 * vnode interlock after VOP_LOCK() drops the vnode 914 * interlock, the other thread will be unable to drop the 915 * vnode lock before our VOP_LOCK() call fails. 916 */ 917 if (vp->v_usecount || 918 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)) || 919 (vp->v_iflag & VI_FREE) != 0 || 920 (vp->v_object != NULL && 921 vp->v_object->resident_page_count > trigger)) { 922 VOP_UNLOCK(vp, LK_INTERLOCK); 923 vdrop(vp); 924 goto next_iter_mntunlocked; 925 } 926 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 927 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 928 counter_u64_add(recycles_count, 1); 929 vgonel(vp); 930 VOP_UNLOCK(vp, 0); 931 vdropl(vp); 932 done++; 933 next_iter_mntunlocked: 934 if (!should_yield()) 935 goto relock_mnt; 936 goto yield; 937 next_iter: 938 if (!should_yield()) 939 continue; 940 MNT_IUNLOCK(mp); 941 yield: 942 kern_yield(PRI_USER); 943 relock_mnt: 944 MNT_ILOCK(mp); 945 } 946 MNT_IUNLOCK(mp); 947 vn_finished_write(mp); 948 return done; 949 } 950 951 static int max_vnlru_free = 10000; /* limit on vnode free requests per call */ 952 SYSCTL_INT(_debug, OID_AUTO, max_vnlru_free, CTLFLAG_RW, &max_vnlru_free, 953 0, 954 "limit on vnode free requests per call to the vnlru_free routine"); 955 956 /* 957 * Attempt to reduce the free list by the requested amount. 958 */ 959 static void 960 vnlru_free_locked(int count, struct vfsops *mnt_op) 961 { 962 struct vnode *vp; 963 struct mount *mp; 964 bool tried_batches; 965 966 tried_batches = false; 967 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 968 if (count > max_vnlru_free) 969 count = max_vnlru_free; 970 for (; count > 0; count--) { 971 vp = TAILQ_FIRST(&vnode_free_list); 972 /* 973 * The list can be modified while the free_list_mtx 974 * has been dropped and vp could be NULL here. 975 */ 976 if (vp == NULL) { 977 if (tried_batches) 978 break; 979 mtx_unlock(&vnode_free_list_mtx); 980 vnlru_return_batches(mnt_op); 981 tried_batches = true; 982 mtx_lock(&vnode_free_list_mtx); 983 continue; 984 } 985 986 VNASSERT(vp->v_op != NULL, vp, 987 ("vnlru_free: vnode already reclaimed.")); 988 KASSERT((vp->v_iflag & VI_FREE) != 0, 989 ("Removing vnode not on freelist")); 990 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 991 ("Mangling active vnode")); 992 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 993 994 /* 995 * Don't recycle if our vnode is from different type 996 * of mount point. Note that mp is type-safe, the 997 * check does not reach unmapped address even if 998 * vnode is reclaimed. 999 * Don't recycle if we can't get the interlock without 1000 * blocking. 1001 */ 1002 if ((mnt_op != NULL && (mp = vp->v_mount) != NULL && 1003 mp->mnt_op != mnt_op) || !VI_TRYLOCK(vp)) { 1004 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 1005 continue; 1006 } 1007 VNASSERT((vp->v_iflag & VI_FREE) != 0 && vp->v_holdcnt == 0, 1008 vp, ("vp inconsistent on freelist")); 1009 1010 /* 1011 * The clear of VI_FREE prevents activation of the 1012 * vnode. There is no sense in putting the vnode on 1013 * the mount point active list, only to remove it 1014 * later during recycling. Inline the relevant part 1015 * of vholdl(), to avoid triggering assertions or 1016 * activating. 1017 */ 1018 freevnodes--; 1019 vp->v_iflag &= ~VI_FREE; 1020 refcount_acquire(&vp->v_holdcnt); 1021 1022 mtx_unlock(&vnode_free_list_mtx); 1023 VI_UNLOCK(vp); 1024 vtryrecycle(vp); 1025 /* 1026 * If the recycled succeeded this vdrop will actually free 1027 * the vnode. If not it will simply place it back on 1028 * the free list. 1029 */ 1030 vdrop(vp); 1031 mtx_lock(&vnode_free_list_mtx); 1032 } 1033 } 1034 1035 void 1036 vnlru_free(int count, struct vfsops *mnt_op) 1037 { 1038 1039 mtx_lock(&vnode_free_list_mtx); 1040 vnlru_free_locked(count, mnt_op); 1041 mtx_unlock(&vnode_free_list_mtx); 1042 } 1043 1044 1045 /* XXX some names and initialization are bad for limits and watermarks. */ 1046 static int 1047 vspace(void) 1048 { 1049 int space; 1050 1051 gapvnodes = imax(desiredvnodes - wantfreevnodes, 100); 1052 vhiwat = gapvnodes / 11; /* 9% -- just under the 10% in vlrureclaim() */ 1053 vlowat = vhiwat / 2; 1054 if (numvnodes > desiredvnodes) 1055 return (0); 1056 space = desiredvnodes - numvnodes; 1057 if (freevnodes > wantfreevnodes) 1058 space += freevnodes - wantfreevnodes; 1059 return (space); 1060 } 1061 1062 static void 1063 vnlru_return_batch_locked(struct mount *mp) 1064 { 1065 struct vnode *vp; 1066 1067 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 1068 1069 if (mp->mnt_tmpfreevnodelistsize == 0) 1070 return; 1071 1072 TAILQ_FOREACH(vp, &mp->mnt_tmpfreevnodelist, v_actfreelist) { 1073 VNASSERT((vp->v_mflag & VMP_TMPMNTFREELIST) != 0, vp, 1074 ("vnode without VMP_TMPMNTFREELIST on mnt_tmpfreevnodelist")); 1075 vp->v_mflag &= ~VMP_TMPMNTFREELIST; 1076 } 1077 mtx_lock(&vnode_free_list_mtx); 1078 TAILQ_CONCAT(&vnode_free_list, &mp->mnt_tmpfreevnodelist, v_actfreelist); 1079 freevnodes += mp->mnt_tmpfreevnodelistsize; 1080 mtx_unlock(&vnode_free_list_mtx); 1081 mp->mnt_tmpfreevnodelistsize = 0; 1082 } 1083 1084 static void 1085 vnlru_return_batch(struct mount *mp) 1086 { 1087 1088 mtx_lock(&mp->mnt_listmtx); 1089 vnlru_return_batch_locked(mp); 1090 mtx_unlock(&mp->mnt_listmtx); 1091 } 1092 1093 static void 1094 vnlru_return_batches(struct vfsops *mnt_op) 1095 { 1096 struct mount *mp, *nmp; 1097 bool need_unbusy; 1098 1099 mtx_lock(&mountlist_mtx); 1100 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 1101 need_unbusy = false; 1102 if (mnt_op != NULL && mp->mnt_op != mnt_op) 1103 goto next; 1104 if (mp->mnt_tmpfreevnodelistsize == 0) 1105 goto next; 1106 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) == 0) { 1107 vnlru_return_batch(mp); 1108 need_unbusy = true; 1109 mtx_lock(&mountlist_mtx); 1110 } 1111 next: 1112 nmp = TAILQ_NEXT(mp, mnt_list); 1113 if (need_unbusy) 1114 vfs_unbusy(mp); 1115 } 1116 mtx_unlock(&mountlist_mtx); 1117 } 1118 1119 /* 1120 * Attempt to recycle vnodes in a context that is always safe to block. 1121 * Calling vlrurecycle() from the bowels of filesystem code has some 1122 * interesting deadlock problems. 1123 */ 1124 static struct proc *vnlruproc; 1125 static int vnlruproc_sig; 1126 1127 static void 1128 vnlru_proc(void) 1129 { 1130 struct mount *mp, *nmp; 1131 unsigned long onumvnodes; 1132 int done, force, reclaim_nc_src, trigger, usevnodes; 1133 1134 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, vnlruproc, 1135 SHUTDOWN_PRI_FIRST); 1136 1137 force = 0; 1138 for (;;) { 1139 kproc_suspend_check(vnlruproc); 1140 mtx_lock(&vnode_free_list_mtx); 1141 /* 1142 * If numvnodes is too large (due to desiredvnodes being 1143 * adjusted using its sysctl, or emergency growth), first 1144 * try to reduce it by discarding from the free list. 1145 */ 1146 if (numvnodes > desiredvnodes) 1147 vnlru_free_locked(numvnodes - desiredvnodes, NULL); 1148 /* 1149 * Sleep if the vnode cache is in a good state. This is 1150 * when it is not over-full and has space for about a 4% 1151 * or 9% expansion (by growing its size or inexcessively 1152 * reducing its free list). Otherwise, try to reclaim 1153 * space for a 10% expansion. 1154 */ 1155 if (vstir && force == 0) { 1156 force = 1; 1157 vstir = 0; 1158 } 1159 if (vspace() >= vlowat && force == 0) { 1160 vnlruproc_sig = 0; 1161 wakeup(&vnlruproc_sig); 1162 msleep(vnlruproc, &vnode_free_list_mtx, 1163 PVFS|PDROP, "vlruwt", hz); 1164 continue; 1165 } 1166 mtx_unlock(&vnode_free_list_mtx); 1167 done = 0; 1168 onumvnodes = numvnodes; 1169 /* 1170 * Calculate parameters for recycling. These are the same 1171 * throughout the loop to give some semblance of fairness. 1172 * The trigger point is to avoid recycling vnodes with lots 1173 * of resident pages. We aren't trying to free memory; we 1174 * are trying to recycle or at least free vnodes. 1175 */ 1176 if (numvnodes <= desiredvnodes) 1177 usevnodes = numvnodes - freevnodes; 1178 else 1179 usevnodes = numvnodes; 1180 if (usevnodes <= 0) 1181 usevnodes = 1; 1182 /* 1183 * The trigger value is is chosen to give a conservatively 1184 * large value to ensure that it alone doesn't prevent 1185 * making progress. The value can easily be so large that 1186 * it is effectively infinite in some congested and 1187 * misconfigured cases, and this is necessary. Normally 1188 * it is about 8 to 100 (pages), which is quite large. 1189 */ 1190 trigger = vm_cnt.v_page_count * 2 / usevnodes; 1191 if (force < 2) 1192 trigger = vsmalltrigger; 1193 reclaim_nc_src = force >= 3; 1194 mtx_lock(&mountlist_mtx); 1195 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 1196 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 1197 nmp = TAILQ_NEXT(mp, mnt_list); 1198 continue; 1199 } 1200 done += vlrureclaim(mp, reclaim_nc_src, trigger); 1201 mtx_lock(&mountlist_mtx); 1202 nmp = TAILQ_NEXT(mp, mnt_list); 1203 vfs_unbusy(mp); 1204 } 1205 mtx_unlock(&mountlist_mtx); 1206 if (onumvnodes > desiredvnodes && numvnodes <= desiredvnodes) 1207 uma_reclaim(); 1208 if (done == 0) { 1209 if (force == 0 || force == 1) { 1210 force = 2; 1211 continue; 1212 } 1213 if (force == 2) { 1214 force = 3; 1215 continue; 1216 } 1217 force = 0; 1218 vnlru_nowhere++; 1219 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 1220 } else 1221 kern_yield(PRI_USER); 1222 /* 1223 * After becoming active to expand above low water, keep 1224 * active until above high water. 1225 */ 1226 force = vspace() < vhiwat; 1227 } 1228 } 1229 1230 static struct kproc_desc vnlru_kp = { 1231 "vnlru", 1232 vnlru_proc, 1233 &vnlruproc 1234 }; 1235 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 1236 &vnlru_kp); 1237 1238 /* 1239 * Routines having to do with the management of the vnode table. 1240 */ 1241 1242 /* 1243 * Try to recycle a freed vnode. We abort if anyone picks up a reference 1244 * before we actually vgone(). This function must be called with the vnode 1245 * held to prevent the vnode from being returned to the free list midway 1246 * through vgone(). 1247 */ 1248 static int 1249 vtryrecycle(struct vnode *vp) 1250 { 1251 struct mount *vnmp; 1252 1253 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 1254 VNASSERT(vp->v_holdcnt, vp, 1255 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 1256 /* 1257 * This vnode may found and locked via some other list, if so we 1258 * can't recycle it yet. 1259 */ 1260 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 1261 CTR2(KTR_VFS, 1262 "%s: impossible to recycle, vp %p lock is already held", 1263 __func__, vp); 1264 return (EWOULDBLOCK); 1265 } 1266 /* 1267 * Don't recycle if its filesystem is being suspended. 1268 */ 1269 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 1270 VOP_UNLOCK(vp, 0); 1271 CTR2(KTR_VFS, 1272 "%s: impossible to recycle, cannot start the write for %p", 1273 __func__, vp); 1274 return (EBUSY); 1275 } 1276 /* 1277 * If we got this far, we need to acquire the interlock and see if 1278 * anyone picked up this vnode from another list. If not, we will 1279 * mark it with DOOMED via vgonel() so that anyone who does find it 1280 * will skip over it. 1281 */ 1282 VI_LOCK(vp); 1283 if (vp->v_usecount) { 1284 VOP_UNLOCK(vp, LK_INTERLOCK); 1285 vn_finished_write(vnmp); 1286 CTR2(KTR_VFS, 1287 "%s: impossible to recycle, %p is already referenced", 1288 __func__, vp); 1289 return (EBUSY); 1290 } 1291 if ((vp->v_iflag & VI_DOOMED) == 0) { 1292 counter_u64_add(recycles_count, 1); 1293 vgonel(vp); 1294 } 1295 VOP_UNLOCK(vp, LK_INTERLOCK); 1296 vn_finished_write(vnmp); 1297 return (0); 1298 } 1299 1300 static void 1301 vcheckspace(void) 1302 { 1303 1304 if (vspace() < vlowat && vnlruproc_sig == 0) { 1305 vnlruproc_sig = 1; 1306 wakeup(vnlruproc); 1307 } 1308 } 1309 1310 /* 1311 * Wait if necessary for space for a new vnode. 1312 */ 1313 static int 1314 getnewvnode_wait(int suspended) 1315 { 1316 1317 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 1318 if (numvnodes >= desiredvnodes) { 1319 if (suspended) { 1320 /* 1321 * The file system is being suspended. We cannot 1322 * risk a deadlock here, so allow allocation of 1323 * another vnode even if this would give too many. 1324 */ 1325 return (0); 1326 } 1327 if (vnlruproc_sig == 0) { 1328 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 1329 wakeup(vnlruproc); 1330 } 1331 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 1332 "vlruwk", hz); 1333 } 1334 /* Post-adjust like the pre-adjust in getnewvnode(). */ 1335 if (numvnodes + 1 > desiredvnodes && freevnodes > 1) 1336 vnlru_free_locked(1, NULL); 1337 return (numvnodes >= desiredvnodes ? ENFILE : 0); 1338 } 1339 1340 /* 1341 * This hack is fragile, and probably not needed any more now that the 1342 * watermark handling works. 1343 */ 1344 void 1345 getnewvnode_reserve(u_int count) 1346 { 1347 struct thread *td; 1348 1349 /* Pre-adjust like the pre-adjust in getnewvnode(), with any count. */ 1350 /* XXX no longer so quick, but this part is not racy. */ 1351 mtx_lock(&vnode_free_list_mtx); 1352 if (numvnodes + count > desiredvnodes && freevnodes > wantfreevnodes) 1353 vnlru_free_locked(ulmin(numvnodes + count - desiredvnodes, 1354 freevnodes - wantfreevnodes), NULL); 1355 mtx_unlock(&vnode_free_list_mtx); 1356 1357 td = curthread; 1358 /* First try to be quick and racy. */ 1359 if (atomic_fetchadd_long(&numvnodes, count) + count <= desiredvnodes) { 1360 td->td_vp_reserv += count; 1361 vcheckspace(); /* XXX no longer so quick, but more racy */ 1362 return; 1363 } else 1364 atomic_subtract_long(&numvnodes, count); 1365 1366 mtx_lock(&vnode_free_list_mtx); 1367 while (count > 0) { 1368 if (getnewvnode_wait(0) == 0) { 1369 count--; 1370 td->td_vp_reserv++; 1371 atomic_add_long(&numvnodes, 1); 1372 } 1373 } 1374 vcheckspace(); 1375 mtx_unlock(&vnode_free_list_mtx); 1376 } 1377 1378 /* 1379 * This hack is fragile, especially if desiredvnodes or wantvnodes are 1380 * misconfgured or changed significantly. Reducing desiredvnodes below 1381 * the reserved amount should cause bizarre behaviour like reducing it 1382 * below the number of active vnodes -- the system will try to reduce 1383 * numvnodes to match, but should fail, so the subtraction below should 1384 * not overflow. 1385 */ 1386 void 1387 getnewvnode_drop_reserve(void) 1388 { 1389 struct thread *td; 1390 1391 td = curthread; 1392 atomic_subtract_long(&numvnodes, td->td_vp_reserv); 1393 td->td_vp_reserv = 0; 1394 } 1395 1396 /* 1397 * Return the next vnode from the free list. 1398 */ 1399 int 1400 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 1401 struct vnode **vpp) 1402 { 1403 struct vnode *vp; 1404 struct thread *td; 1405 struct lock_object *lo; 1406 static int cyclecount; 1407 int error; 1408 1409 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1410 vp = NULL; 1411 td = curthread; 1412 if (td->td_vp_reserv > 0) { 1413 td->td_vp_reserv -= 1; 1414 goto alloc; 1415 } 1416 mtx_lock(&vnode_free_list_mtx); 1417 if (numvnodes < desiredvnodes) 1418 cyclecount = 0; 1419 else if (cyclecount++ >= freevnodes) { 1420 cyclecount = 0; 1421 vstir = 1; 1422 } 1423 /* 1424 * Grow the vnode cache if it will not be above its target max 1425 * after growing. Otherwise, if the free list is nonempty, try 1426 * to reclaim 1 item from it before growing the cache (possibly 1427 * above its target max if the reclamation failed or is delayed). 1428 * Otherwise, wait for some space. In all cases, schedule 1429 * vnlru_proc() if we are getting short of space. The watermarks 1430 * should be chosen so that we never wait or even reclaim from 1431 * the free list to below its target minimum. 1432 */ 1433 if (numvnodes + 1 <= desiredvnodes) 1434 ; 1435 else if (freevnodes > 0) 1436 vnlru_free_locked(1, NULL); 1437 else { 1438 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1439 MNTK_SUSPEND)); 1440 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1441 if (error != 0) { 1442 mtx_unlock(&vnode_free_list_mtx); 1443 return (error); 1444 } 1445 #endif 1446 } 1447 vcheckspace(); 1448 atomic_add_long(&numvnodes, 1); 1449 mtx_unlock(&vnode_free_list_mtx); 1450 alloc: 1451 counter_u64_add(vnodes_created, 1); 1452 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK); 1453 /* 1454 * Locks are given the generic name "vnode" when created. 1455 * Follow the historic practice of using the filesystem 1456 * name when they allocated, e.g., "zfs", "ufs", "nfs, etc. 1457 * 1458 * Locks live in a witness group keyed on their name. Thus, 1459 * when a lock is renamed, it must also move from the witness 1460 * group of its old name to the witness group of its new name. 1461 * 1462 * The change only needs to be made when the vnode moves 1463 * from one filesystem type to another. We ensure that each 1464 * filesystem use a single static name pointer for its tag so 1465 * that we can compare pointers rather than doing a strcmp(). 1466 */ 1467 lo = &vp->v_vnlock->lock_object; 1468 if (lo->lo_name != tag) { 1469 lo->lo_name = tag; 1470 WITNESS_DESTROY(lo); 1471 WITNESS_INIT(lo, tag); 1472 } 1473 /* 1474 * By default, don't allow shared locks unless filesystems opt-in. 1475 */ 1476 vp->v_vnlock->lock_object.lo_flags |= LK_NOSHARE; 1477 /* 1478 * Finalize various vnode identity bits. 1479 */ 1480 KASSERT(vp->v_object == NULL, ("stale v_object %p", vp)); 1481 KASSERT(vp->v_lockf == NULL, ("stale v_lockf %p", vp)); 1482 KASSERT(vp->v_pollinfo == NULL, ("stale v_pollinfo %p", vp)); 1483 vp->v_type = VNON; 1484 vp->v_tag = tag; 1485 vp->v_op = vops; 1486 v_init_counters(vp); 1487 vp->v_bufobj.bo_ops = &buf_ops_bio; 1488 #ifdef DIAGNOSTIC 1489 if (mp == NULL && vops != &dead_vnodeops) 1490 printf("NULL mp in getnewvnode(9), tag %s\n", tag); 1491 #endif 1492 #ifdef MAC 1493 mac_vnode_init(vp); 1494 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1495 mac_vnode_associate_singlelabel(mp, vp); 1496 #endif 1497 if (mp != NULL) { 1498 vp->v_bufobj.bo_bsize = mp->mnt_stat.f_iosize; 1499 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1500 vp->v_vflag |= VV_NOKNOTE; 1501 } 1502 1503 /* 1504 * For the filesystems which do not use vfs_hash_insert(), 1505 * still initialize v_hash to have vfs_hash_index() useful. 1506 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1507 * its own hashing. 1508 */ 1509 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1510 1511 *vpp = vp; 1512 return (0); 1513 } 1514 1515 /* 1516 * Delete from old mount point vnode list, if on one. 1517 */ 1518 static void 1519 delmntque(struct vnode *vp) 1520 { 1521 struct mount *mp; 1522 int active; 1523 1524 mp = vp->v_mount; 1525 if (mp == NULL) 1526 return; 1527 MNT_ILOCK(mp); 1528 VI_LOCK(vp); 1529 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1530 ("Active vnode list size %d > Vnode list size %d", 1531 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1532 active = vp->v_iflag & VI_ACTIVE; 1533 vp->v_iflag &= ~VI_ACTIVE; 1534 if (active) { 1535 mtx_lock(&mp->mnt_listmtx); 1536 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1537 mp->mnt_activevnodelistsize--; 1538 mtx_unlock(&mp->mnt_listmtx); 1539 } 1540 vp->v_mount = NULL; 1541 VI_UNLOCK(vp); 1542 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1543 ("bad mount point vnode list size")); 1544 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1545 mp->mnt_nvnodelistsize--; 1546 MNT_REL(mp); 1547 MNT_IUNLOCK(mp); 1548 } 1549 1550 static void 1551 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1552 { 1553 1554 vp->v_data = NULL; 1555 vp->v_op = &dead_vnodeops; 1556 vgone(vp); 1557 vput(vp); 1558 } 1559 1560 /* 1561 * Insert into list of vnodes for the new mount point, if available. 1562 */ 1563 int 1564 insmntque1(struct vnode *vp, struct mount *mp, 1565 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1566 { 1567 1568 KASSERT(vp->v_mount == NULL, 1569 ("insmntque: vnode already on per mount vnode list")); 1570 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1571 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1572 1573 /* 1574 * We acquire the vnode interlock early to ensure that the 1575 * vnode cannot be recycled by another process releasing a 1576 * holdcnt on it before we get it on both the vnode list 1577 * and the active vnode list. The mount mutex protects only 1578 * manipulation of the vnode list and the vnode freelist 1579 * mutex protects only manipulation of the active vnode list. 1580 * Hence the need to hold the vnode interlock throughout. 1581 */ 1582 MNT_ILOCK(mp); 1583 VI_LOCK(vp); 1584 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1585 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1586 mp->mnt_nvnodelistsize == 0)) && 1587 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1588 VI_UNLOCK(vp); 1589 MNT_IUNLOCK(mp); 1590 if (dtr != NULL) 1591 dtr(vp, dtr_arg); 1592 return (EBUSY); 1593 } 1594 vp->v_mount = mp; 1595 MNT_REF(mp); 1596 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1597 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1598 ("neg mount point vnode list size")); 1599 mp->mnt_nvnodelistsize++; 1600 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1601 ("Activating already active vnode")); 1602 vp->v_iflag |= VI_ACTIVE; 1603 mtx_lock(&mp->mnt_listmtx); 1604 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1605 mp->mnt_activevnodelistsize++; 1606 mtx_unlock(&mp->mnt_listmtx); 1607 VI_UNLOCK(vp); 1608 MNT_IUNLOCK(mp); 1609 return (0); 1610 } 1611 1612 int 1613 insmntque(struct vnode *vp, struct mount *mp) 1614 { 1615 1616 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1617 } 1618 1619 /* 1620 * Flush out and invalidate all buffers associated with a bufobj 1621 * Called with the underlying object locked. 1622 */ 1623 int 1624 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1625 { 1626 int error; 1627 1628 BO_LOCK(bo); 1629 if (flags & V_SAVE) { 1630 error = bufobj_wwait(bo, slpflag, slptimeo); 1631 if (error) { 1632 BO_UNLOCK(bo); 1633 return (error); 1634 } 1635 if (bo->bo_dirty.bv_cnt > 0) { 1636 BO_UNLOCK(bo); 1637 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1638 return (error); 1639 /* 1640 * XXX We could save a lock/unlock if this was only 1641 * enabled under INVARIANTS 1642 */ 1643 BO_LOCK(bo); 1644 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1645 panic("vinvalbuf: dirty bufs"); 1646 } 1647 } 1648 /* 1649 * If you alter this loop please notice that interlock is dropped and 1650 * reacquired in flushbuflist. Special care is needed to ensure that 1651 * no race conditions occur from this. 1652 */ 1653 do { 1654 error = flushbuflist(&bo->bo_clean, 1655 flags, bo, slpflag, slptimeo); 1656 if (error == 0 && !(flags & V_CLEANONLY)) 1657 error = flushbuflist(&bo->bo_dirty, 1658 flags, bo, slpflag, slptimeo); 1659 if (error != 0 && error != EAGAIN) { 1660 BO_UNLOCK(bo); 1661 return (error); 1662 } 1663 } while (error != 0); 1664 1665 /* 1666 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1667 * have write I/O in-progress but if there is a VM object then the 1668 * VM object can also have read-I/O in-progress. 1669 */ 1670 do { 1671 bufobj_wwait(bo, 0, 0); 1672 if ((flags & V_VMIO) == 0) { 1673 BO_UNLOCK(bo); 1674 if (bo->bo_object != NULL) { 1675 VM_OBJECT_WLOCK(bo->bo_object); 1676 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1677 VM_OBJECT_WUNLOCK(bo->bo_object); 1678 } 1679 BO_LOCK(bo); 1680 } 1681 } while (bo->bo_numoutput > 0); 1682 BO_UNLOCK(bo); 1683 1684 /* 1685 * Destroy the copy in the VM cache, too. 1686 */ 1687 if (bo->bo_object != NULL && 1688 (flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO)) == 0) { 1689 VM_OBJECT_WLOCK(bo->bo_object); 1690 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1691 OBJPR_CLEANONLY : 0); 1692 VM_OBJECT_WUNLOCK(bo->bo_object); 1693 } 1694 1695 #ifdef INVARIANTS 1696 BO_LOCK(bo); 1697 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO | 1698 V_ALLOWCLEAN)) == 0 && (bo->bo_dirty.bv_cnt > 0 || 1699 bo->bo_clean.bv_cnt > 0)) 1700 panic("vinvalbuf: flush failed"); 1701 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO)) == 0 && 1702 bo->bo_dirty.bv_cnt > 0) 1703 panic("vinvalbuf: flush dirty failed"); 1704 BO_UNLOCK(bo); 1705 #endif 1706 return (0); 1707 } 1708 1709 /* 1710 * Flush out and invalidate all buffers associated with a vnode. 1711 * Called with the underlying object locked. 1712 */ 1713 int 1714 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1715 { 1716 1717 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1718 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1719 if (vp->v_object != NULL && vp->v_object->handle != vp) 1720 return (0); 1721 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1722 } 1723 1724 /* 1725 * Flush out buffers on the specified list. 1726 * 1727 */ 1728 static int 1729 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1730 int slptimeo) 1731 { 1732 struct buf *bp, *nbp; 1733 int retval, error; 1734 daddr_t lblkno; 1735 b_xflags_t xflags; 1736 1737 ASSERT_BO_WLOCKED(bo); 1738 1739 retval = 0; 1740 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1741 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1742 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1743 continue; 1744 } 1745 if (nbp != NULL) { 1746 lblkno = nbp->b_lblkno; 1747 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN); 1748 } 1749 retval = EAGAIN; 1750 error = BUF_TIMELOCK(bp, 1751 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo), 1752 "flushbuf", slpflag, slptimeo); 1753 if (error) { 1754 BO_LOCK(bo); 1755 return (error != ENOLCK ? error : EAGAIN); 1756 } 1757 KASSERT(bp->b_bufobj == bo, 1758 ("bp %p wrong b_bufobj %p should be %p", 1759 bp, bp->b_bufobj, bo)); 1760 /* 1761 * XXX Since there are no node locks for NFS, I 1762 * believe there is a slight chance that a delayed 1763 * write will occur while sleeping just above, so 1764 * check for it. 1765 */ 1766 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1767 (flags & V_SAVE)) { 1768 bremfree(bp); 1769 bp->b_flags |= B_ASYNC; 1770 bwrite(bp); 1771 BO_LOCK(bo); 1772 return (EAGAIN); /* XXX: why not loop ? */ 1773 } 1774 bremfree(bp); 1775 bp->b_flags |= (B_INVAL | B_RELBUF); 1776 bp->b_flags &= ~B_ASYNC; 1777 brelse(bp); 1778 BO_LOCK(bo); 1779 if (nbp == NULL) 1780 break; 1781 nbp = gbincore(bo, lblkno); 1782 if (nbp == NULL || (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1783 != xflags) 1784 break; /* nbp invalid */ 1785 } 1786 return (retval); 1787 } 1788 1789 int 1790 bnoreuselist(struct bufv *bufv, struct bufobj *bo, daddr_t startn, daddr_t endn) 1791 { 1792 struct buf *bp; 1793 int error; 1794 daddr_t lblkno; 1795 1796 ASSERT_BO_LOCKED(bo); 1797 1798 for (lblkno = startn;;) { 1799 again: 1800 bp = BUF_PCTRIE_LOOKUP_GE(&bufv->bv_root, lblkno); 1801 if (bp == NULL || bp->b_lblkno >= endn || 1802 bp->b_lblkno < startn) 1803 break; 1804 error = BUF_TIMELOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL | 1805 LK_INTERLOCK, BO_LOCKPTR(bo), "brlsfl", 0, 0); 1806 if (error != 0) { 1807 BO_RLOCK(bo); 1808 if (error == ENOLCK) 1809 goto again; 1810 return (error); 1811 } 1812 KASSERT(bp->b_bufobj == bo, 1813 ("bp %p wrong b_bufobj %p should be %p", 1814 bp, bp->b_bufobj, bo)); 1815 lblkno = bp->b_lblkno + 1; 1816 if ((bp->b_flags & B_MANAGED) == 0) 1817 bremfree(bp); 1818 bp->b_flags |= B_RELBUF; 1819 /* 1820 * In the VMIO case, use the B_NOREUSE flag to hint that the 1821 * pages backing each buffer in the range are unlikely to be 1822 * reused. Dirty buffers will have the hint applied once 1823 * they've been written. 1824 */ 1825 if (bp->b_vp->v_object != NULL) 1826 bp->b_flags |= B_NOREUSE; 1827 brelse(bp); 1828 BO_RLOCK(bo); 1829 } 1830 return (0); 1831 } 1832 1833 /* 1834 * Truncate a file's buffer and pages to a specified length. This 1835 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1836 * sync activity. 1837 */ 1838 int 1839 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1840 { 1841 struct buf *bp, *nbp; 1842 int anyfreed; 1843 int trunclbn; 1844 struct bufobj *bo; 1845 1846 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1847 vp, cred, blksize, (uintmax_t)length); 1848 1849 /* 1850 * Round up to the *next* lbn. 1851 */ 1852 trunclbn = howmany(length, blksize); 1853 1854 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1855 restart: 1856 bo = &vp->v_bufobj; 1857 BO_LOCK(bo); 1858 anyfreed = 1; 1859 for (;anyfreed;) { 1860 anyfreed = 0; 1861 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1862 if (bp->b_lblkno < trunclbn) 1863 continue; 1864 if (BUF_LOCK(bp, 1865 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1866 BO_LOCKPTR(bo)) == ENOLCK) 1867 goto restart; 1868 1869 bremfree(bp); 1870 bp->b_flags |= (B_INVAL | B_RELBUF); 1871 bp->b_flags &= ~B_ASYNC; 1872 brelse(bp); 1873 anyfreed = 1; 1874 1875 BO_LOCK(bo); 1876 if (nbp != NULL && 1877 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1878 (nbp->b_vp != vp) || 1879 (nbp->b_flags & B_DELWRI))) { 1880 BO_UNLOCK(bo); 1881 goto restart; 1882 } 1883 } 1884 1885 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1886 if (bp->b_lblkno < trunclbn) 1887 continue; 1888 if (BUF_LOCK(bp, 1889 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1890 BO_LOCKPTR(bo)) == ENOLCK) 1891 goto restart; 1892 bremfree(bp); 1893 bp->b_flags |= (B_INVAL | B_RELBUF); 1894 bp->b_flags &= ~B_ASYNC; 1895 brelse(bp); 1896 anyfreed = 1; 1897 1898 BO_LOCK(bo); 1899 if (nbp != NULL && 1900 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1901 (nbp->b_vp != vp) || 1902 (nbp->b_flags & B_DELWRI) == 0)) { 1903 BO_UNLOCK(bo); 1904 goto restart; 1905 } 1906 } 1907 } 1908 1909 if (length > 0) { 1910 restartsync: 1911 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1912 if (bp->b_lblkno > 0) 1913 continue; 1914 /* 1915 * Since we hold the vnode lock this should only 1916 * fail if we're racing with the buf daemon. 1917 */ 1918 if (BUF_LOCK(bp, 1919 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1920 BO_LOCKPTR(bo)) == ENOLCK) { 1921 goto restart; 1922 } 1923 VNASSERT((bp->b_flags & B_DELWRI), vp, 1924 ("buf(%p) on dirty queue without DELWRI", bp)); 1925 1926 bremfree(bp); 1927 bawrite(bp); 1928 BO_LOCK(bo); 1929 goto restartsync; 1930 } 1931 } 1932 1933 bufobj_wwait(bo, 0, 0); 1934 BO_UNLOCK(bo); 1935 vnode_pager_setsize(vp, length); 1936 1937 return (0); 1938 } 1939 1940 static void 1941 buf_vlist_remove(struct buf *bp) 1942 { 1943 struct bufv *bv; 1944 1945 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1946 ASSERT_BO_WLOCKED(bp->b_bufobj); 1947 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1948 (BX_VNDIRTY|BX_VNCLEAN), 1949 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1950 if (bp->b_xflags & BX_VNDIRTY) 1951 bv = &bp->b_bufobj->bo_dirty; 1952 else 1953 bv = &bp->b_bufobj->bo_clean; 1954 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno); 1955 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1956 bv->bv_cnt--; 1957 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1958 } 1959 1960 /* 1961 * Add the buffer to the sorted clean or dirty block list. 1962 * 1963 * NOTE: xflags is passed as a constant, optimizing this inline function! 1964 */ 1965 static void 1966 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1967 { 1968 struct bufv *bv; 1969 struct buf *n; 1970 int error; 1971 1972 ASSERT_BO_WLOCKED(bo); 1973 KASSERT((xflags & BX_VNDIRTY) == 0 || (bo->bo_flag & BO_DEAD) == 0, 1974 ("dead bo %p", bo)); 1975 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1976 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1977 bp->b_xflags |= xflags; 1978 if (xflags & BX_VNDIRTY) 1979 bv = &bo->bo_dirty; 1980 else 1981 bv = &bo->bo_clean; 1982 1983 /* 1984 * Keep the list ordered. Optimize empty list insertion. Assume 1985 * we tend to grow at the tail so lookup_le should usually be cheaper 1986 * than _ge. 1987 */ 1988 if (bv->bv_cnt == 0 || 1989 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno) 1990 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1991 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL) 1992 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs); 1993 else 1994 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs); 1995 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp); 1996 if (error) 1997 panic("buf_vlist_add: Preallocated nodes insufficient."); 1998 bv->bv_cnt++; 1999 } 2000 2001 /* 2002 * Look up a buffer using the buffer tries. 2003 */ 2004 struct buf * 2005 gbincore(struct bufobj *bo, daddr_t lblkno) 2006 { 2007 struct buf *bp; 2008 2009 ASSERT_BO_LOCKED(bo); 2010 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno); 2011 if (bp != NULL) 2012 return (bp); 2013 return BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno); 2014 } 2015 2016 /* 2017 * Associate a buffer with a vnode. 2018 */ 2019 void 2020 bgetvp(struct vnode *vp, struct buf *bp) 2021 { 2022 struct bufobj *bo; 2023 2024 bo = &vp->v_bufobj; 2025 ASSERT_BO_WLOCKED(bo); 2026 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 2027 2028 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 2029 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 2030 ("bgetvp: bp already attached! %p", bp)); 2031 2032 vhold(vp); 2033 bp->b_vp = vp; 2034 bp->b_bufobj = bo; 2035 /* 2036 * Insert onto list for new vnode. 2037 */ 2038 buf_vlist_add(bp, bo, BX_VNCLEAN); 2039 } 2040 2041 /* 2042 * Disassociate a buffer from a vnode. 2043 */ 2044 void 2045 brelvp(struct buf *bp) 2046 { 2047 struct bufobj *bo; 2048 struct vnode *vp; 2049 2050 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 2051 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 2052 2053 /* 2054 * Delete from old vnode list, if on one. 2055 */ 2056 vp = bp->b_vp; /* XXX */ 2057 bo = bp->b_bufobj; 2058 BO_LOCK(bo); 2059 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2060 buf_vlist_remove(bp); 2061 else 2062 panic("brelvp: Buffer %p not on queue.", bp); 2063 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2064 bo->bo_flag &= ~BO_ONWORKLST; 2065 mtx_lock(&sync_mtx); 2066 LIST_REMOVE(bo, bo_synclist); 2067 syncer_worklist_len--; 2068 mtx_unlock(&sync_mtx); 2069 } 2070 bp->b_vp = NULL; 2071 bp->b_bufobj = NULL; 2072 BO_UNLOCK(bo); 2073 vdrop(vp); 2074 } 2075 2076 /* 2077 * Add an item to the syncer work queue. 2078 */ 2079 static void 2080 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 2081 { 2082 int slot; 2083 2084 ASSERT_BO_WLOCKED(bo); 2085 2086 mtx_lock(&sync_mtx); 2087 if (bo->bo_flag & BO_ONWORKLST) 2088 LIST_REMOVE(bo, bo_synclist); 2089 else { 2090 bo->bo_flag |= BO_ONWORKLST; 2091 syncer_worklist_len++; 2092 } 2093 2094 if (delay > syncer_maxdelay - 2) 2095 delay = syncer_maxdelay - 2; 2096 slot = (syncer_delayno + delay) & syncer_mask; 2097 2098 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 2099 mtx_unlock(&sync_mtx); 2100 } 2101 2102 static int 2103 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 2104 { 2105 int error, len; 2106 2107 mtx_lock(&sync_mtx); 2108 len = syncer_worklist_len - sync_vnode_count; 2109 mtx_unlock(&sync_mtx); 2110 error = SYSCTL_OUT(req, &len, sizeof(len)); 2111 return (error); 2112 } 2113 2114 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 2115 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 2116 2117 static struct proc *updateproc; 2118 static void sched_sync(void); 2119 static struct kproc_desc up_kp = { 2120 "syncer", 2121 sched_sync, 2122 &updateproc 2123 }; 2124 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 2125 2126 static int 2127 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 2128 { 2129 struct vnode *vp; 2130 struct mount *mp; 2131 2132 *bo = LIST_FIRST(slp); 2133 if (*bo == NULL) 2134 return (0); 2135 vp = bo2vnode(*bo); 2136 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 2137 return (1); 2138 /* 2139 * We use vhold in case the vnode does not 2140 * successfully sync. vhold prevents the vnode from 2141 * going away when we unlock the sync_mtx so that 2142 * we can acquire the vnode interlock. 2143 */ 2144 vholdl(vp); 2145 mtx_unlock(&sync_mtx); 2146 VI_UNLOCK(vp); 2147 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 2148 vdrop(vp); 2149 mtx_lock(&sync_mtx); 2150 return (*bo == LIST_FIRST(slp)); 2151 } 2152 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2153 (void) VOP_FSYNC(vp, MNT_LAZY, td); 2154 VOP_UNLOCK(vp, 0); 2155 vn_finished_write(mp); 2156 BO_LOCK(*bo); 2157 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 2158 /* 2159 * Put us back on the worklist. The worklist 2160 * routine will remove us from our current 2161 * position and then add us back in at a later 2162 * position. 2163 */ 2164 vn_syncer_add_to_worklist(*bo, syncdelay); 2165 } 2166 BO_UNLOCK(*bo); 2167 vdrop(vp); 2168 mtx_lock(&sync_mtx); 2169 return (0); 2170 } 2171 2172 static int first_printf = 1; 2173 2174 /* 2175 * System filesystem synchronizer daemon. 2176 */ 2177 static void 2178 sched_sync(void) 2179 { 2180 struct synclist *next, *slp; 2181 struct bufobj *bo; 2182 long starttime; 2183 struct thread *td = curthread; 2184 int last_work_seen; 2185 int net_worklist_len; 2186 int syncer_final_iter; 2187 int error; 2188 2189 last_work_seen = 0; 2190 syncer_final_iter = 0; 2191 syncer_state = SYNCER_RUNNING; 2192 starttime = time_uptime; 2193 td->td_pflags |= TDP_NORUNNINGBUF; 2194 2195 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 2196 SHUTDOWN_PRI_LAST); 2197 2198 mtx_lock(&sync_mtx); 2199 for (;;) { 2200 if (syncer_state == SYNCER_FINAL_DELAY && 2201 syncer_final_iter == 0) { 2202 mtx_unlock(&sync_mtx); 2203 kproc_suspend_check(td->td_proc); 2204 mtx_lock(&sync_mtx); 2205 } 2206 net_worklist_len = syncer_worklist_len - sync_vnode_count; 2207 if (syncer_state != SYNCER_RUNNING && 2208 starttime != time_uptime) { 2209 if (first_printf) { 2210 printf("\nSyncing disks, vnodes remaining... "); 2211 first_printf = 0; 2212 } 2213 printf("%d ", net_worklist_len); 2214 } 2215 starttime = time_uptime; 2216 2217 /* 2218 * Push files whose dirty time has expired. Be careful 2219 * of interrupt race on slp queue. 2220 * 2221 * Skip over empty worklist slots when shutting down. 2222 */ 2223 do { 2224 slp = &syncer_workitem_pending[syncer_delayno]; 2225 syncer_delayno += 1; 2226 if (syncer_delayno == syncer_maxdelay) 2227 syncer_delayno = 0; 2228 next = &syncer_workitem_pending[syncer_delayno]; 2229 /* 2230 * If the worklist has wrapped since the 2231 * it was emptied of all but syncer vnodes, 2232 * switch to the FINAL_DELAY state and run 2233 * for one more second. 2234 */ 2235 if (syncer_state == SYNCER_SHUTTING_DOWN && 2236 net_worklist_len == 0 && 2237 last_work_seen == syncer_delayno) { 2238 syncer_state = SYNCER_FINAL_DELAY; 2239 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 2240 } 2241 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 2242 syncer_worklist_len > 0); 2243 2244 /* 2245 * Keep track of the last time there was anything 2246 * on the worklist other than syncer vnodes. 2247 * Return to the SHUTTING_DOWN state if any 2248 * new work appears. 2249 */ 2250 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 2251 last_work_seen = syncer_delayno; 2252 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 2253 syncer_state = SYNCER_SHUTTING_DOWN; 2254 while (!LIST_EMPTY(slp)) { 2255 error = sync_vnode(slp, &bo, td); 2256 if (error == 1) { 2257 LIST_REMOVE(bo, bo_synclist); 2258 LIST_INSERT_HEAD(next, bo, bo_synclist); 2259 continue; 2260 } 2261 2262 if (first_printf == 0) { 2263 /* 2264 * Drop the sync mutex, because some watchdog 2265 * drivers need to sleep while patting 2266 */ 2267 mtx_unlock(&sync_mtx); 2268 wdog_kern_pat(WD_LASTVAL); 2269 mtx_lock(&sync_mtx); 2270 } 2271 2272 } 2273 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 2274 syncer_final_iter--; 2275 /* 2276 * The variable rushjob allows the kernel to speed up the 2277 * processing of the filesystem syncer process. A rushjob 2278 * value of N tells the filesystem syncer to process the next 2279 * N seconds worth of work on its queue ASAP. Currently rushjob 2280 * is used by the soft update code to speed up the filesystem 2281 * syncer process when the incore state is getting so far 2282 * ahead of the disk that the kernel memory pool is being 2283 * threatened with exhaustion. 2284 */ 2285 if (rushjob > 0) { 2286 rushjob -= 1; 2287 continue; 2288 } 2289 /* 2290 * Just sleep for a short period of time between 2291 * iterations when shutting down to allow some I/O 2292 * to happen. 2293 * 2294 * If it has taken us less than a second to process the 2295 * current work, then wait. Otherwise start right over 2296 * again. We can still lose time if any single round 2297 * takes more than two seconds, but it does not really 2298 * matter as we are just trying to generally pace the 2299 * filesystem activity. 2300 */ 2301 if (syncer_state != SYNCER_RUNNING || 2302 time_uptime == starttime) { 2303 thread_lock(td); 2304 sched_prio(td, PPAUSE); 2305 thread_unlock(td); 2306 } 2307 if (syncer_state != SYNCER_RUNNING) 2308 cv_timedwait(&sync_wakeup, &sync_mtx, 2309 hz / SYNCER_SHUTDOWN_SPEEDUP); 2310 else if (time_uptime == starttime) 2311 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 2312 } 2313 } 2314 2315 /* 2316 * Request the syncer daemon to speed up its work. 2317 * We never push it to speed up more than half of its 2318 * normal turn time, otherwise it could take over the cpu. 2319 */ 2320 int 2321 speedup_syncer(void) 2322 { 2323 int ret = 0; 2324 2325 mtx_lock(&sync_mtx); 2326 if (rushjob < syncdelay / 2) { 2327 rushjob += 1; 2328 stat_rush_requests += 1; 2329 ret = 1; 2330 } 2331 mtx_unlock(&sync_mtx); 2332 cv_broadcast(&sync_wakeup); 2333 return (ret); 2334 } 2335 2336 /* 2337 * Tell the syncer to speed up its work and run though its work 2338 * list several times, then tell it to shut down. 2339 */ 2340 static void 2341 syncer_shutdown(void *arg, int howto) 2342 { 2343 2344 if (howto & RB_NOSYNC) 2345 return; 2346 mtx_lock(&sync_mtx); 2347 syncer_state = SYNCER_SHUTTING_DOWN; 2348 rushjob = 0; 2349 mtx_unlock(&sync_mtx); 2350 cv_broadcast(&sync_wakeup); 2351 kproc_shutdown(arg, howto); 2352 } 2353 2354 void 2355 syncer_suspend(void) 2356 { 2357 2358 syncer_shutdown(updateproc, 0); 2359 } 2360 2361 void 2362 syncer_resume(void) 2363 { 2364 2365 mtx_lock(&sync_mtx); 2366 first_printf = 1; 2367 syncer_state = SYNCER_RUNNING; 2368 mtx_unlock(&sync_mtx); 2369 cv_broadcast(&sync_wakeup); 2370 kproc_resume(updateproc); 2371 } 2372 2373 /* 2374 * Reassign a buffer from one vnode to another. 2375 * Used to assign file specific control information 2376 * (indirect blocks) to the vnode to which they belong. 2377 */ 2378 void 2379 reassignbuf(struct buf *bp) 2380 { 2381 struct vnode *vp; 2382 struct bufobj *bo; 2383 int delay; 2384 #ifdef INVARIANTS 2385 struct bufv *bv; 2386 #endif 2387 2388 vp = bp->b_vp; 2389 bo = bp->b_bufobj; 2390 ++reassignbufcalls; 2391 2392 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 2393 bp, bp->b_vp, bp->b_flags); 2394 /* 2395 * B_PAGING flagged buffers cannot be reassigned because their vp 2396 * is not fully linked in. 2397 */ 2398 if (bp->b_flags & B_PAGING) 2399 panic("cannot reassign paging buffer"); 2400 2401 /* 2402 * Delete from old vnode list, if on one. 2403 */ 2404 BO_LOCK(bo); 2405 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2406 buf_vlist_remove(bp); 2407 else 2408 panic("reassignbuf: Buffer %p not on queue.", bp); 2409 /* 2410 * If dirty, put on list of dirty buffers; otherwise insert onto list 2411 * of clean buffers. 2412 */ 2413 if (bp->b_flags & B_DELWRI) { 2414 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2415 switch (vp->v_type) { 2416 case VDIR: 2417 delay = dirdelay; 2418 break; 2419 case VCHR: 2420 delay = metadelay; 2421 break; 2422 default: 2423 delay = filedelay; 2424 } 2425 vn_syncer_add_to_worklist(bo, delay); 2426 } 2427 buf_vlist_add(bp, bo, BX_VNDIRTY); 2428 } else { 2429 buf_vlist_add(bp, bo, BX_VNCLEAN); 2430 2431 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2432 mtx_lock(&sync_mtx); 2433 LIST_REMOVE(bo, bo_synclist); 2434 syncer_worklist_len--; 2435 mtx_unlock(&sync_mtx); 2436 bo->bo_flag &= ~BO_ONWORKLST; 2437 } 2438 } 2439 #ifdef INVARIANTS 2440 bv = &bo->bo_clean; 2441 bp = TAILQ_FIRST(&bv->bv_hd); 2442 KASSERT(bp == NULL || bp->b_bufobj == bo, 2443 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2444 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2445 KASSERT(bp == NULL || bp->b_bufobj == bo, 2446 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2447 bv = &bo->bo_dirty; 2448 bp = TAILQ_FIRST(&bv->bv_hd); 2449 KASSERT(bp == NULL || bp->b_bufobj == bo, 2450 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2451 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2452 KASSERT(bp == NULL || bp->b_bufobj == bo, 2453 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2454 #endif 2455 BO_UNLOCK(bo); 2456 } 2457 2458 static void 2459 v_init_counters(struct vnode *vp) 2460 { 2461 2462 VNASSERT(vp->v_type == VNON && vp->v_data == NULL && vp->v_iflag == 0, 2463 vp, ("%s called for an initialized vnode", __FUNCTION__)); 2464 ASSERT_VI_UNLOCKED(vp, __FUNCTION__); 2465 2466 refcount_init(&vp->v_holdcnt, 1); 2467 refcount_init(&vp->v_usecount, 1); 2468 } 2469 2470 static void 2471 v_incr_usecount_locked(struct vnode *vp) 2472 { 2473 2474 ASSERT_VI_LOCKED(vp, __func__); 2475 if ((vp->v_iflag & VI_OWEINACT) != 0) { 2476 VNASSERT(vp->v_usecount == 0, vp, 2477 ("vnode with usecount and VI_OWEINACT set")); 2478 vp->v_iflag &= ~VI_OWEINACT; 2479 } 2480 refcount_acquire(&vp->v_usecount); 2481 v_incr_devcount(vp); 2482 } 2483 2484 /* 2485 * Increment the use count on the vnode, taking care to reference 2486 * the driver's usecount if this is a chardev. 2487 */ 2488 static void 2489 v_incr_usecount(struct vnode *vp) 2490 { 2491 2492 ASSERT_VI_UNLOCKED(vp, __func__); 2493 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2494 2495 if (vp->v_type != VCHR && 2496 refcount_acquire_if_not_zero(&vp->v_usecount)) { 2497 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp, 2498 ("vnode with usecount and VI_OWEINACT set")); 2499 } else { 2500 VI_LOCK(vp); 2501 v_incr_usecount_locked(vp); 2502 VI_UNLOCK(vp); 2503 } 2504 } 2505 2506 /* 2507 * Increment si_usecount of the associated device, if any. 2508 */ 2509 static void 2510 v_incr_devcount(struct vnode *vp) 2511 { 2512 2513 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2514 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2515 dev_lock(); 2516 vp->v_rdev->si_usecount++; 2517 dev_unlock(); 2518 } 2519 } 2520 2521 /* 2522 * Decrement si_usecount of the associated device, if any. 2523 */ 2524 static void 2525 v_decr_devcount(struct vnode *vp) 2526 { 2527 2528 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2529 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2530 dev_lock(); 2531 vp->v_rdev->si_usecount--; 2532 dev_unlock(); 2533 } 2534 } 2535 2536 /* 2537 * Grab a particular vnode from the free list, increment its 2538 * reference count and lock it. VI_DOOMED is set if the vnode 2539 * is being destroyed. Only callers who specify LK_RETRY will 2540 * see doomed vnodes. If inactive processing was delayed in 2541 * vput try to do it here. 2542 * 2543 * Notes on lockless counter manipulation: 2544 * _vhold, vputx and other routines make various decisions based 2545 * on either holdcnt or usecount being 0. As long as either counter 2546 * is not transitioning 0->1 nor 1->0, the manipulation can be done 2547 * with atomic operations. Otherwise the interlock is taken covering 2548 * both the atomic and additional actions. 2549 */ 2550 int 2551 vget(struct vnode *vp, int flags, struct thread *td) 2552 { 2553 int error, oweinact; 2554 2555 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2556 ("vget: invalid lock operation")); 2557 2558 if ((flags & LK_INTERLOCK) != 0) 2559 ASSERT_VI_LOCKED(vp, __func__); 2560 else 2561 ASSERT_VI_UNLOCKED(vp, __func__); 2562 if ((flags & LK_VNHELD) != 0) 2563 VNASSERT((vp->v_holdcnt > 0), vp, 2564 ("vget: LK_VNHELD passed but vnode not held")); 2565 2566 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2567 2568 if ((flags & LK_VNHELD) == 0) 2569 _vhold(vp, (flags & LK_INTERLOCK) != 0); 2570 2571 if ((error = vn_lock(vp, flags)) != 0) { 2572 vdrop(vp); 2573 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2574 vp); 2575 return (error); 2576 } 2577 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2578 panic("vget: vn_lock failed to return ENOENT\n"); 2579 /* 2580 * We don't guarantee that any particular close will 2581 * trigger inactive processing so just make a best effort 2582 * here at preventing a reference to a removed file. If 2583 * we don't succeed no harm is done. 2584 * 2585 * Upgrade our holdcnt to a usecount. 2586 */ 2587 if (vp->v_type == VCHR || 2588 !refcount_acquire_if_not_zero(&vp->v_usecount)) { 2589 VI_LOCK(vp); 2590 if ((vp->v_iflag & VI_OWEINACT) == 0) { 2591 oweinact = 0; 2592 } else { 2593 oweinact = 1; 2594 vp->v_iflag &= ~VI_OWEINACT; 2595 } 2596 refcount_acquire(&vp->v_usecount); 2597 v_incr_devcount(vp); 2598 if (oweinact && VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2599 (flags & LK_NOWAIT) == 0) 2600 vinactive(vp, td); 2601 VI_UNLOCK(vp); 2602 } 2603 return (0); 2604 } 2605 2606 /* 2607 * Increase the reference (use) and hold count of a vnode. 2608 * This will also remove the vnode from the free list if it is presently free. 2609 */ 2610 void 2611 vref(struct vnode *vp) 2612 { 2613 2614 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2615 _vhold(vp, false); 2616 v_incr_usecount(vp); 2617 } 2618 2619 void 2620 vrefl(struct vnode *vp) 2621 { 2622 2623 ASSERT_VI_LOCKED(vp, __func__); 2624 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2625 _vhold(vp, true); 2626 v_incr_usecount_locked(vp); 2627 } 2628 2629 void 2630 vrefact(struct vnode *vp) 2631 { 2632 2633 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2634 if (__predict_false(vp->v_type == VCHR)) { 2635 VNASSERT(vp->v_holdcnt > 0 && vp->v_usecount > 0, vp, 2636 ("%s: wrong ref counts", __func__)); 2637 vref(vp); 2638 return; 2639 } 2640 #ifdef INVARIANTS 2641 int old = atomic_fetchadd_int(&vp->v_holdcnt, 1); 2642 VNASSERT(old > 0, vp, ("%s: wrong hold count", __func__)); 2643 old = atomic_fetchadd_int(&vp->v_usecount, 1); 2644 VNASSERT(old > 0, vp, ("%s: wrong use count", __func__)); 2645 #else 2646 refcount_acquire(&vp->v_holdcnt); 2647 refcount_acquire(&vp->v_usecount); 2648 #endif 2649 } 2650 2651 /* 2652 * Return reference count of a vnode. 2653 * 2654 * The results of this call are only guaranteed when some mechanism is used to 2655 * stop other processes from gaining references to the vnode. This may be the 2656 * case if the caller holds the only reference. This is also useful when stale 2657 * data is acceptable as race conditions may be accounted for by some other 2658 * means. 2659 */ 2660 int 2661 vrefcnt(struct vnode *vp) 2662 { 2663 2664 return (vp->v_usecount); 2665 } 2666 2667 #define VPUTX_VRELE 1 2668 #define VPUTX_VPUT 2 2669 #define VPUTX_VUNREF 3 2670 2671 /* 2672 * Decrement the use and hold counts for a vnode. 2673 * 2674 * See an explanation near vget() as to why atomic operation is safe. 2675 */ 2676 static void 2677 vputx(struct vnode *vp, int func) 2678 { 2679 int error; 2680 2681 KASSERT(vp != NULL, ("vputx: null vp")); 2682 if (func == VPUTX_VUNREF) 2683 ASSERT_VOP_LOCKED(vp, "vunref"); 2684 else if (func == VPUTX_VPUT) 2685 ASSERT_VOP_LOCKED(vp, "vput"); 2686 else 2687 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2688 ASSERT_VI_UNLOCKED(vp, __func__); 2689 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2690 2691 if (vp->v_type != VCHR && 2692 refcount_release_if_not_last(&vp->v_usecount)) { 2693 if (func == VPUTX_VPUT) 2694 VOP_UNLOCK(vp, 0); 2695 vdrop(vp); 2696 return; 2697 } 2698 2699 VI_LOCK(vp); 2700 2701 /* 2702 * We want to hold the vnode until the inactive finishes to 2703 * prevent vgone() races. We drop the use count here and the 2704 * hold count below when we're done. 2705 */ 2706 if (!refcount_release(&vp->v_usecount) || 2707 (vp->v_iflag & VI_DOINGINACT)) { 2708 if (func == VPUTX_VPUT) 2709 VOP_UNLOCK(vp, 0); 2710 v_decr_devcount(vp); 2711 vdropl(vp); 2712 return; 2713 } 2714 2715 v_decr_devcount(vp); 2716 2717 error = 0; 2718 2719 if (vp->v_usecount != 0) { 2720 vn_printf(vp, "vputx: usecount not zero for vnode "); 2721 panic("vputx: usecount not zero"); 2722 } 2723 2724 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2725 2726 /* 2727 * We must call VOP_INACTIVE with the node locked. Mark 2728 * as VI_DOINGINACT to avoid recursion. 2729 */ 2730 vp->v_iflag |= VI_OWEINACT; 2731 switch (func) { 2732 case VPUTX_VRELE: 2733 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2734 VI_LOCK(vp); 2735 break; 2736 case VPUTX_VPUT: 2737 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2738 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2739 LK_NOWAIT); 2740 VI_LOCK(vp); 2741 } 2742 break; 2743 case VPUTX_VUNREF: 2744 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2745 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK); 2746 VI_LOCK(vp); 2747 } 2748 break; 2749 } 2750 VNASSERT(vp->v_usecount == 0 || (vp->v_iflag & VI_OWEINACT) == 0, vp, 2751 ("vnode with usecount and VI_OWEINACT set")); 2752 if (error == 0) { 2753 if (vp->v_iflag & VI_OWEINACT) 2754 vinactive(vp, curthread); 2755 if (func != VPUTX_VUNREF) 2756 VOP_UNLOCK(vp, 0); 2757 } 2758 vdropl(vp); 2759 } 2760 2761 /* 2762 * Vnode put/release. 2763 * If count drops to zero, call inactive routine and return to freelist. 2764 */ 2765 void 2766 vrele(struct vnode *vp) 2767 { 2768 2769 vputx(vp, VPUTX_VRELE); 2770 } 2771 2772 /* 2773 * Release an already locked vnode. This give the same effects as 2774 * unlock+vrele(), but takes less time and avoids releasing and 2775 * re-aquiring the lock (as vrele() acquires the lock internally.) 2776 */ 2777 void 2778 vput(struct vnode *vp) 2779 { 2780 2781 vputx(vp, VPUTX_VPUT); 2782 } 2783 2784 /* 2785 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2786 */ 2787 void 2788 vunref(struct vnode *vp) 2789 { 2790 2791 vputx(vp, VPUTX_VUNREF); 2792 } 2793 2794 /* 2795 * Increase the hold count and activate if this is the first reference. 2796 */ 2797 void 2798 _vhold(struct vnode *vp, bool locked) 2799 { 2800 struct mount *mp; 2801 2802 if (locked) 2803 ASSERT_VI_LOCKED(vp, __func__); 2804 else 2805 ASSERT_VI_UNLOCKED(vp, __func__); 2806 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2807 if (!locked) { 2808 if (refcount_acquire_if_not_zero(&vp->v_holdcnt)) { 2809 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2810 ("_vhold: vnode with holdcnt is free")); 2811 return; 2812 } 2813 VI_LOCK(vp); 2814 } 2815 if ((vp->v_iflag & VI_FREE) == 0) { 2816 refcount_acquire(&vp->v_holdcnt); 2817 if (!locked) 2818 VI_UNLOCK(vp); 2819 return; 2820 } 2821 VNASSERT(vp->v_holdcnt == 0, vp, 2822 ("%s: wrong hold count", __func__)); 2823 VNASSERT(vp->v_op != NULL, vp, 2824 ("%s: vnode already reclaimed.", __func__)); 2825 /* 2826 * Remove a vnode from the free list, mark it as in use, 2827 * and put it on the active list. 2828 */ 2829 VNASSERT(vp->v_mount != NULL, vp, 2830 ("_vhold: vnode not on per mount vnode list")); 2831 mp = vp->v_mount; 2832 mtx_lock(&mp->mnt_listmtx); 2833 if ((vp->v_mflag & VMP_TMPMNTFREELIST) != 0) { 2834 TAILQ_REMOVE(&mp->mnt_tmpfreevnodelist, vp, v_actfreelist); 2835 mp->mnt_tmpfreevnodelistsize--; 2836 vp->v_mflag &= ~VMP_TMPMNTFREELIST; 2837 } else { 2838 mtx_lock(&vnode_free_list_mtx); 2839 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2840 freevnodes--; 2841 mtx_unlock(&vnode_free_list_mtx); 2842 } 2843 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2844 ("Activating already active vnode")); 2845 vp->v_iflag &= ~VI_FREE; 2846 vp->v_iflag |= VI_ACTIVE; 2847 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2848 mp->mnt_activevnodelistsize++; 2849 mtx_unlock(&mp->mnt_listmtx); 2850 refcount_acquire(&vp->v_holdcnt); 2851 if (!locked) 2852 VI_UNLOCK(vp); 2853 } 2854 2855 /* 2856 * Drop the hold count of the vnode. If this is the last reference to 2857 * the vnode we place it on the free list unless it has been vgone'd 2858 * (marked VI_DOOMED) in which case we will free it. 2859 * 2860 * Because the vnode vm object keeps a hold reference on the vnode if 2861 * there is at least one resident non-cached page, the vnode cannot 2862 * leave the active list without the page cleanup done. 2863 */ 2864 void 2865 _vdrop(struct vnode *vp, bool locked) 2866 { 2867 struct bufobj *bo; 2868 struct mount *mp; 2869 int active; 2870 2871 if (locked) 2872 ASSERT_VI_LOCKED(vp, __func__); 2873 else 2874 ASSERT_VI_UNLOCKED(vp, __func__); 2875 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2876 if ((int)vp->v_holdcnt <= 0) 2877 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2878 if (!locked) { 2879 if (refcount_release_if_not_last(&vp->v_holdcnt)) 2880 return; 2881 VI_LOCK(vp); 2882 } 2883 if (refcount_release(&vp->v_holdcnt) == 0) { 2884 VI_UNLOCK(vp); 2885 return; 2886 } 2887 if ((vp->v_iflag & VI_DOOMED) == 0) { 2888 /* 2889 * Mark a vnode as free: remove it from its active list 2890 * and put it up for recycling on the freelist. 2891 */ 2892 VNASSERT(vp->v_op != NULL, vp, 2893 ("vdropl: vnode already reclaimed.")); 2894 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2895 ("vnode already free")); 2896 VNASSERT(vp->v_holdcnt == 0, vp, 2897 ("vdropl: freeing when we shouldn't")); 2898 active = vp->v_iflag & VI_ACTIVE; 2899 if ((vp->v_iflag & VI_OWEINACT) == 0) { 2900 vp->v_iflag &= ~VI_ACTIVE; 2901 mp = vp->v_mount; 2902 if (mp != NULL) { 2903 mtx_lock(&mp->mnt_listmtx); 2904 if (active) { 2905 TAILQ_REMOVE(&mp->mnt_activevnodelist, 2906 vp, v_actfreelist); 2907 mp->mnt_activevnodelistsize--; 2908 } 2909 TAILQ_INSERT_TAIL(&mp->mnt_tmpfreevnodelist, 2910 vp, v_actfreelist); 2911 mp->mnt_tmpfreevnodelistsize++; 2912 vp->v_iflag |= VI_FREE; 2913 vp->v_mflag |= VMP_TMPMNTFREELIST; 2914 VI_UNLOCK(vp); 2915 if (mp->mnt_tmpfreevnodelistsize >= 2916 mnt_free_list_batch) 2917 vnlru_return_batch_locked(mp); 2918 mtx_unlock(&mp->mnt_listmtx); 2919 } else { 2920 VNASSERT(active == 0, vp, 2921 ("vdropl: active vnode not on per mount " 2922 "vnode list")); 2923 mtx_lock(&vnode_free_list_mtx); 2924 TAILQ_INSERT_TAIL(&vnode_free_list, vp, 2925 v_actfreelist); 2926 freevnodes++; 2927 vp->v_iflag |= VI_FREE; 2928 VI_UNLOCK(vp); 2929 mtx_unlock(&vnode_free_list_mtx); 2930 } 2931 } else { 2932 VI_UNLOCK(vp); 2933 counter_u64_add(free_owe_inact, 1); 2934 } 2935 return; 2936 } 2937 /* 2938 * The vnode has been marked for destruction, so free it. 2939 * 2940 * The vnode will be returned to the zone where it will 2941 * normally remain until it is needed for another vnode. We 2942 * need to cleanup (or verify that the cleanup has already 2943 * been done) any residual data left from its current use 2944 * so as not to contaminate the freshly allocated vnode. 2945 */ 2946 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2947 atomic_subtract_long(&numvnodes, 1); 2948 bo = &vp->v_bufobj; 2949 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2950 ("cleaned vnode still on the free list.")); 2951 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2952 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2953 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2954 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2955 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2956 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2957 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 2958 ("clean blk trie not empty")); 2959 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2960 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 2961 ("dirty blk trie not empty")); 2962 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2963 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2964 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2965 VNASSERT(TAILQ_EMPTY(&vp->v_rl.rl_waiters), vp, 2966 ("Dangling rangelock waiters")); 2967 VI_UNLOCK(vp); 2968 #ifdef MAC 2969 mac_vnode_destroy(vp); 2970 #endif 2971 if (vp->v_pollinfo != NULL) { 2972 destroy_vpollinfo(vp->v_pollinfo); 2973 vp->v_pollinfo = NULL; 2974 } 2975 #ifdef INVARIANTS 2976 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2977 vp->v_op = NULL; 2978 #endif 2979 vp->v_mountedhere = NULL; 2980 vp->v_unpcb = NULL; 2981 vp->v_rdev = NULL; 2982 vp->v_fifoinfo = NULL; 2983 vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0; 2984 vp->v_iflag = 0; 2985 vp->v_vflag = 0; 2986 bo->bo_flag = 0; 2987 uma_zfree(vnode_zone, vp); 2988 } 2989 2990 /* 2991 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2992 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2993 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2994 * failed lock upgrade. 2995 */ 2996 void 2997 vinactive(struct vnode *vp, struct thread *td) 2998 { 2999 struct vm_object *obj; 3000 3001 ASSERT_VOP_ELOCKED(vp, "vinactive"); 3002 ASSERT_VI_LOCKED(vp, "vinactive"); 3003 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 3004 ("vinactive: recursed on VI_DOINGINACT")); 3005 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3006 vp->v_iflag |= VI_DOINGINACT; 3007 vp->v_iflag &= ~VI_OWEINACT; 3008 VI_UNLOCK(vp); 3009 /* 3010 * Before moving off the active list, we must be sure that any 3011 * modified pages are converted into the vnode's dirty 3012 * buffers, since these will no longer be checked once the 3013 * vnode is on the inactive list. 3014 * 3015 * The write-out of the dirty pages is asynchronous. At the 3016 * point that VOP_INACTIVE() is called, there could still be 3017 * pending I/O and dirty pages in the object. 3018 */ 3019 if ((obj = vp->v_object) != NULL && (vp->v_vflag & VV_NOSYNC) == 0 && 3020 (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 3021 VM_OBJECT_WLOCK(obj); 3022 vm_object_page_clean(obj, 0, 0, 0); 3023 VM_OBJECT_WUNLOCK(obj); 3024 } 3025 VOP_INACTIVE(vp, td); 3026 VI_LOCK(vp); 3027 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 3028 ("vinactive: lost VI_DOINGINACT")); 3029 vp->v_iflag &= ~VI_DOINGINACT; 3030 } 3031 3032 /* 3033 * Remove any vnodes in the vnode table belonging to mount point mp. 3034 * 3035 * If FORCECLOSE is not specified, there should not be any active ones, 3036 * return error if any are found (nb: this is a user error, not a 3037 * system error). If FORCECLOSE is specified, detach any active vnodes 3038 * that are found. 3039 * 3040 * If WRITECLOSE is set, only flush out regular file vnodes open for 3041 * writing. 3042 * 3043 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 3044 * 3045 * `rootrefs' specifies the base reference count for the root vnode 3046 * of this filesystem. The root vnode is considered busy if its 3047 * v_usecount exceeds this value. On a successful return, vflush(, td) 3048 * will call vrele() on the root vnode exactly rootrefs times. 3049 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 3050 * be zero. 3051 */ 3052 #ifdef DIAGNOSTIC 3053 static int busyprt = 0; /* print out busy vnodes */ 3054 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 3055 #endif 3056 3057 int 3058 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 3059 { 3060 struct vnode *vp, *mvp, *rootvp = NULL; 3061 struct vattr vattr; 3062 int busy = 0, error; 3063 3064 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 3065 rootrefs, flags); 3066 if (rootrefs > 0) { 3067 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 3068 ("vflush: bad args")); 3069 /* 3070 * Get the filesystem root vnode. We can vput() it 3071 * immediately, since with rootrefs > 0, it won't go away. 3072 */ 3073 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 3074 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 3075 __func__, error); 3076 return (error); 3077 } 3078 vput(rootvp); 3079 } 3080 loop: 3081 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 3082 vholdl(vp); 3083 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 3084 if (error) { 3085 vdrop(vp); 3086 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 3087 goto loop; 3088 } 3089 /* 3090 * Skip over a vnodes marked VV_SYSTEM. 3091 */ 3092 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 3093 VOP_UNLOCK(vp, 0); 3094 vdrop(vp); 3095 continue; 3096 } 3097 /* 3098 * If WRITECLOSE is set, flush out unlinked but still open 3099 * files (even if open only for reading) and regular file 3100 * vnodes open for writing. 3101 */ 3102 if (flags & WRITECLOSE) { 3103 if (vp->v_object != NULL) { 3104 VM_OBJECT_WLOCK(vp->v_object); 3105 vm_object_page_clean(vp->v_object, 0, 0, 0); 3106 VM_OBJECT_WUNLOCK(vp->v_object); 3107 } 3108 error = VOP_FSYNC(vp, MNT_WAIT, td); 3109 if (error != 0) { 3110 VOP_UNLOCK(vp, 0); 3111 vdrop(vp); 3112 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 3113 return (error); 3114 } 3115 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 3116 VI_LOCK(vp); 3117 3118 if ((vp->v_type == VNON || 3119 (error == 0 && vattr.va_nlink > 0)) && 3120 (vp->v_writecount == 0 || vp->v_type != VREG)) { 3121 VOP_UNLOCK(vp, 0); 3122 vdropl(vp); 3123 continue; 3124 } 3125 } else 3126 VI_LOCK(vp); 3127 /* 3128 * With v_usecount == 0, all we need to do is clear out the 3129 * vnode data structures and we are done. 3130 * 3131 * If FORCECLOSE is set, forcibly close the vnode. 3132 */ 3133 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 3134 vgonel(vp); 3135 } else { 3136 busy++; 3137 #ifdef DIAGNOSTIC 3138 if (busyprt) 3139 vn_printf(vp, "vflush: busy vnode "); 3140 #endif 3141 } 3142 VOP_UNLOCK(vp, 0); 3143 vdropl(vp); 3144 } 3145 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 3146 /* 3147 * If just the root vnode is busy, and if its refcount 3148 * is equal to `rootrefs', then go ahead and kill it. 3149 */ 3150 VI_LOCK(rootvp); 3151 KASSERT(busy > 0, ("vflush: not busy")); 3152 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 3153 ("vflush: usecount %d < rootrefs %d", 3154 rootvp->v_usecount, rootrefs)); 3155 if (busy == 1 && rootvp->v_usecount == rootrefs) { 3156 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 3157 vgone(rootvp); 3158 VOP_UNLOCK(rootvp, 0); 3159 busy = 0; 3160 } else 3161 VI_UNLOCK(rootvp); 3162 } 3163 if (busy) { 3164 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 3165 busy); 3166 return (EBUSY); 3167 } 3168 for (; rootrefs > 0; rootrefs--) 3169 vrele(rootvp); 3170 return (0); 3171 } 3172 3173 /* 3174 * Recycle an unused vnode to the front of the free list. 3175 */ 3176 int 3177 vrecycle(struct vnode *vp) 3178 { 3179 int recycled; 3180 3181 VI_LOCK(vp); 3182 recycled = vrecyclel(vp); 3183 VI_UNLOCK(vp); 3184 return (recycled); 3185 } 3186 3187 /* 3188 * vrecycle, with the vp interlock held. 3189 */ 3190 int 3191 vrecyclel(struct vnode *vp) 3192 { 3193 int recycled; 3194 3195 ASSERT_VOP_ELOCKED(vp, __func__); 3196 ASSERT_VI_LOCKED(vp, __func__); 3197 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3198 recycled = 0; 3199 if (vp->v_usecount == 0) { 3200 recycled = 1; 3201 vgonel(vp); 3202 } 3203 return (recycled); 3204 } 3205 3206 /* 3207 * Eliminate all activity associated with a vnode 3208 * in preparation for reuse. 3209 */ 3210 void 3211 vgone(struct vnode *vp) 3212 { 3213 VI_LOCK(vp); 3214 vgonel(vp); 3215 VI_UNLOCK(vp); 3216 } 3217 3218 static void 3219 notify_lowervp_vfs_dummy(struct mount *mp __unused, 3220 struct vnode *lowervp __unused) 3221 { 3222 } 3223 3224 /* 3225 * Notify upper mounts about reclaimed or unlinked vnode. 3226 */ 3227 void 3228 vfs_notify_upper(struct vnode *vp, int event) 3229 { 3230 static struct vfsops vgonel_vfsops = { 3231 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 3232 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 3233 }; 3234 struct mount *mp, *ump, *mmp; 3235 3236 mp = vp->v_mount; 3237 if (mp == NULL) 3238 return; 3239 3240 MNT_ILOCK(mp); 3241 if (TAILQ_EMPTY(&mp->mnt_uppers)) 3242 goto unlock; 3243 MNT_IUNLOCK(mp); 3244 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 3245 mmp->mnt_op = &vgonel_vfsops; 3246 mmp->mnt_kern_flag |= MNTK_MARKER; 3247 MNT_ILOCK(mp); 3248 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 3249 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 3250 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 3251 ump = TAILQ_NEXT(ump, mnt_upper_link); 3252 continue; 3253 } 3254 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 3255 MNT_IUNLOCK(mp); 3256 switch (event) { 3257 case VFS_NOTIFY_UPPER_RECLAIM: 3258 VFS_RECLAIM_LOWERVP(ump, vp); 3259 break; 3260 case VFS_NOTIFY_UPPER_UNLINK: 3261 VFS_UNLINK_LOWERVP(ump, vp); 3262 break; 3263 default: 3264 KASSERT(0, ("invalid event %d", event)); 3265 break; 3266 } 3267 MNT_ILOCK(mp); 3268 ump = TAILQ_NEXT(mmp, mnt_upper_link); 3269 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 3270 } 3271 free(mmp, M_TEMP); 3272 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 3273 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 3274 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 3275 wakeup(&mp->mnt_uppers); 3276 } 3277 unlock: 3278 MNT_IUNLOCK(mp); 3279 } 3280 3281 /* 3282 * vgone, with the vp interlock held. 3283 */ 3284 static void 3285 vgonel(struct vnode *vp) 3286 { 3287 struct thread *td; 3288 int oweinact; 3289 int active; 3290 struct mount *mp; 3291 3292 ASSERT_VOP_ELOCKED(vp, "vgonel"); 3293 ASSERT_VI_LOCKED(vp, "vgonel"); 3294 VNASSERT(vp->v_holdcnt, vp, 3295 ("vgonel: vp %p has no reference.", vp)); 3296 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3297 td = curthread; 3298 3299 /* 3300 * Don't vgonel if we're already doomed. 3301 */ 3302 if (vp->v_iflag & VI_DOOMED) 3303 return; 3304 vp->v_iflag |= VI_DOOMED; 3305 3306 /* 3307 * Check to see if the vnode is in use. If so, we have to call 3308 * VOP_CLOSE() and VOP_INACTIVE(). 3309 */ 3310 active = vp->v_usecount; 3311 oweinact = (vp->v_iflag & VI_OWEINACT); 3312 VI_UNLOCK(vp); 3313 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 3314 3315 /* 3316 * If purging an active vnode, it must be closed and 3317 * deactivated before being reclaimed. 3318 */ 3319 if (active) 3320 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 3321 if (oweinact || active) { 3322 VI_LOCK(vp); 3323 if ((vp->v_iflag & VI_DOINGINACT) == 0) 3324 vinactive(vp, td); 3325 VI_UNLOCK(vp); 3326 } 3327 if (vp->v_type == VSOCK) 3328 vfs_unp_reclaim(vp); 3329 3330 /* 3331 * Clean out any buffers associated with the vnode. 3332 * If the flush fails, just toss the buffers. 3333 */ 3334 mp = NULL; 3335 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 3336 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 3337 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) { 3338 while (vinvalbuf(vp, 0, 0, 0) != 0) 3339 ; 3340 } 3341 3342 BO_LOCK(&vp->v_bufobj); 3343 KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) && 3344 vp->v_bufobj.bo_dirty.bv_cnt == 0 && 3345 TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) && 3346 vp->v_bufobj.bo_clean.bv_cnt == 0, 3347 ("vp %p bufobj not invalidated", vp)); 3348 3349 /* 3350 * For VMIO bufobj, BO_DEAD is set in vm_object_terminate() 3351 * after the object's page queue is flushed. 3352 */ 3353 if (vp->v_bufobj.bo_object == NULL) 3354 vp->v_bufobj.bo_flag |= BO_DEAD; 3355 BO_UNLOCK(&vp->v_bufobj); 3356 3357 /* 3358 * Reclaim the vnode. 3359 */ 3360 if (VOP_RECLAIM(vp, td)) 3361 panic("vgone: cannot reclaim"); 3362 if (mp != NULL) 3363 vn_finished_secondary_write(mp); 3364 VNASSERT(vp->v_object == NULL, vp, 3365 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 3366 /* 3367 * Clear the advisory locks and wake up waiting threads. 3368 */ 3369 (void)VOP_ADVLOCKPURGE(vp); 3370 vp->v_lockf = NULL; 3371 /* 3372 * Delete from old mount point vnode list. 3373 */ 3374 delmntque(vp); 3375 cache_purge(vp); 3376 /* 3377 * Done with purge, reset to the standard lock and invalidate 3378 * the vnode. 3379 */ 3380 VI_LOCK(vp); 3381 vp->v_vnlock = &vp->v_lock; 3382 vp->v_op = &dead_vnodeops; 3383 vp->v_tag = "none"; 3384 vp->v_type = VBAD; 3385 } 3386 3387 /* 3388 * Calculate the total number of references to a special device. 3389 */ 3390 int 3391 vcount(struct vnode *vp) 3392 { 3393 int count; 3394 3395 dev_lock(); 3396 count = vp->v_rdev->si_usecount; 3397 dev_unlock(); 3398 return (count); 3399 } 3400 3401 /* 3402 * Same as above, but using the struct cdev *as argument 3403 */ 3404 int 3405 count_dev(struct cdev *dev) 3406 { 3407 int count; 3408 3409 dev_lock(); 3410 count = dev->si_usecount; 3411 dev_unlock(); 3412 return(count); 3413 } 3414 3415 /* 3416 * Print out a description of a vnode. 3417 */ 3418 static char *typename[] = 3419 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 3420 "VMARKER"}; 3421 3422 void 3423 vn_printf(struct vnode *vp, const char *fmt, ...) 3424 { 3425 va_list ap; 3426 char buf[256], buf2[16]; 3427 u_long flags; 3428 3429 va_start(ap, fmt); 3430 vprintf(fmt, ap); 3431 va_end(ap); 3432 printf("%p: ", (void *)vp); 3433 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 3434 printf(" usecount %d, writecount %d, refcount %d", 3435 vp->v_usecount, vp->v_writecount, vp->v_holdcnt); 3436 switch (vp->v_type) { 3437 case VDIR: 3438 printf(" mountedhere %p\n", vp->v_mountedhere); 3439 break; 3440 case VCHR: 3441 printf(" rdev %p\n", vp->v_rdev); 3442 break; 3443 case VSOCK: 3444 printf(" socket %p\n", vp->v_unpcb); 3445 break; 3446 case VFIFO: 3447 printf(" fifoinfo %p\n", vp->v_fifoinfo); 3448 break; 3449 default: 3450 printf("\n"); 3451 break; 3452 } 3453 buf[0] = '\0'; 3454 buf[1] = '\0'; 3455 if (vp->v_vflag & VV_ROOT) 3456 strlcat(buf, "|VV_ROOT", sizeof(buf)); 3457 if (vp->v_vflag & VV_ISTTY) 3458 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 3459 if (vp->v_vflag & VV_NOSYNC) 3460 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 3461 if (vp->v_vflag & VV_ETERNALDEV) 3462 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 3463 if (vp->v_vflag & VV_CACHEDLABEL) 3464 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 3465 if (vp->v_vflag & VV_TEXT) 3466 strlcat(buf, "|VV_TEXT", sizeof(buf)); 3467 if (vp->v_vflag & VV_COPYONWRITE) 3468 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 3469 if (vp->v_vflag & VV_SYSTEM) 3470 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 3471 if (vp->v_vflag & VV_PROCDEP) 3472 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 3473 if (vp->v_vflag & VV_NOKNOTE) 3474 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 3475 if (vp->v_vflag & VV_DELETED) 3476 strlcat(buf, "|VV_DELETED", sizeof(buf)); 3477 if (vp->v_vflag & VV_MD) 3478 strlcat(buf, "|VV_MD", sizeof(buf)); 3479 if (vp->v_vflag & VV_FORCEINSMQ) 3480 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 3481 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 3482 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 3483 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 3484 if (flags != 0) { 3485 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 3486 strlcat(buf, buf2, sizeof(buf)); 3487 } 3488 if (vp->v_iflag & VI_MOUNT) 3489 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 3490 if (vp->v_iflag & VI_DOOMED) 3491 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 3492 if (vp->v_iflag & VI_FREE) 3493 strlcat(buf, "|VI_FREE", sizeof(buf)); 3494 if (vp->v_iflag & VI_ACTIVE) 3495 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 3496 if (vp->v_iflag & VI_DOINGINACT) 3497 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 3498 if (vp->v_iflag & VI_OWEINACT) 3499 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 3500 flags = vp->v_iflag & ~(VI_MOUNT | VI_DOOMED | VI_FREE | 3501 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 3502 if (flags != 0) { 3503 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 3504 strlcat(buf, buf2, sizeof(buf)); 3505 } 3506 printf(" flags (%s)\n", buf + 1); 3507 if (mtx_owned(VI_MTX(vp))) 3508 printf(" VI_LOCKed"); 3509 if (vp->v_object != NULL) 3510 printf(" v_object %p ref %d pages %d " 3511 "cleanbuf %d dirtybuf %d\n", 3512 vp->v_object, vp->v_object->ref_count, 3513 vp->v_object->resident_page_count, 3514 vp->v_bufobj.bo_clean.bv_cnt, 3515 vp->v_bufobj.bo_dirty.bv_cnt); 3516 printf(" "); 3517 lockmgr_printinfo(vp->v_vnlock); 3518 if (vp->v_data != NULL) 3519 VOP_PRINT(vp); 3520 } 3521 3522 #ifdef DDB 3523 /* 3524 * List all of the locked vnodes in the system. 3525 * Called when debugging the kernel. 3526 */ 3527 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 3528 { 3529 struct mount *mp; 3530 struct vnode *vp; 3531 3532 /* 3533 * Note: because this is DDB, we can't obey the locking semantics 3534 * for these structures, which means we could catch an inconsistent 3535 * state and dereference a nasty pointer. Not much to be done 3536 * about that. 3537 */ 3538 db_printf("Locked vnodes\n"); 3539 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3540 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3541 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp)) 3542 vn_printf(vp, "vnode "); 3543 } 3544 } 3545 } 3546 3547 /* 3548 * Show details about the given vnode. 3549 */ 3550 DB_SHOW_COMMAND(vnode, db_show_vnode) 3551 { 3552 struct vnode *vp; 3553 3554 if (!have_addr) 3555 return; 3556 vp = (struct vnode *)addr; 3557 vn_printf(vp, "vnode "); 3558 } 3559 3560 /* 3561 * Show details about the given mount point. 3562 */ 3563 DB_SHOW_COMMAND(mount, db_show_mount) 3564 { 3565 struct mount *mp; 3566 struct vfsopt *opt; 3567 struct statfs *sp; 3568 struct vnode *vp; 3569 char buf[512]; 3570 uint64_t mflags; 3571 u_int flags; 3572 3573 if (!have_addr) { 3574 /* No address given, print short info about all mount points. */ 3575 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3576 db_printf("%p %s on %s (%s)\n", mp, 3577 mp->mnt_stat.f_mntfromname, 3578 mp->mnt_stat.f_mntonname, 3579 mp->mnt_stat.f_fstypename); 3580 if (db_pager_quit) 3581 break; 3582 } 3583 db_printf("\nMore info: show mount <addr>\n"); 3584 return; 3585 } 3586 3587 mp = (struct mount *)addr; 3588 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 3589 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 3590 3591 buf[0] = '\0'; 3592 mflags = mp->mnt_flag; 3593 #define MNT_FLAG(flag) do { \ 3594 if (mflags & (flag)) { \ 3595 if (buf[0] != '\0') \ 3596 strlcat(buf, ", ", sizeof(buf)); \ 3597 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 3598 mflags &= ~(flag); \ 3599 } \ 3600 } while (0) 3601 MNT_FLAG(MNT_RDONLY); 3602 MNT_FLAG(MNT_SYNCHRONOUS); 3603 MNT_FLAG(MNT_NOEXEC); 3604 MNT_FLAG(MNT_NOSUID); 3605 MNT_FLAG(MNT_NFS4ACLS); 3606 MNT_FLAG(MNT_UNION); 3607 MNT_FLAG(MNT_ASYNC); 3608 MNT_FLAG(MNT_SUIDDIR); 3609 MNT_FLAG(MNT_SOFTDEP); 3610 MNT_FLAG(MNT_NOSYMFOLLOW); 3611 MNT_FLAG(MNT_GJOURNAL); 3612 MNT_FLAG(MNT_MULTILABEL); 3613 MNT_FLAG(MNT_ACLS); 3614 MNT_FLAG(MNT_NOATIME); 3615 MNT_FLAG(MNT_NOCLUSTERR); 3616 MNT_FLAG(MNT_NOCLUSTERW); 3617 MNT_FLAG(MNT_SUJ); 3618 MNT_FLAG(MNT_EXRDONLY); 3619 MNT_FLAG(MNT_EXPORTED); 3620 MNT_FLAG(MNT_DEFEXPORTED); 3621 MNT_FLAG(MNT_EXPORTANON); 3622 MNT_FLAG(MNT_EXKERB); 3623 MNT_FLAG(MNT_EXPUBLIC); 3624 MNT_FLAG(MNT_LOCAL); 3625 MNT_FLAG(MNT_QUOTA); 3626 MNT_FLAG(MNT_ROOTFS); 3627 MNT_FLAG(MNT_USER); 3628 MNT_FLAG(MNT_IGNORE); 3629 MNT_FLAG(MNT_UPDATE); 3630 MNT_FLAG(MNT_DELEXPORT); 3631 MNT_FLAG(MNT_RELOAD); 3632 MNT_FLAG(MNT_FORCE); 3633 MNT_FLAG(MNT_SNAPSHOT); 3634 MNT_FLAG(MNT_BYFSID); 3635 #undef MNT_FLAG 3636 if (mflags != 0) { 3637 if (buf[0] != '\0') 3638 strlcat(buf, ", ", sizeof(buf)); 3639 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3640 "0x%016jx", mflags); 3641 } 3642 db_printf(" mnt_flag = %s\n", buf); 3643 3644 buf[0] = '\0'; 3645 flags = mp->mnt_kern_flag; 3646 #define MNT_KERN_FLAG(flag) do { \ 3647 if (flags & (flag)) { \ 3648 if (buf[0] != '\0') \ 3649 strlcat(buf, ", ", sizeof(buf)); \ 3650 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3651 flags &= ~(flag); \ 3652 } \ 3653 } while (0) 3654 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3655 MNT_KERN_FLAG(MNTK_ASYNC); 3656 MNT_KERN_FLAG(MNTK_SOFTDEP); 3657 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3658 MNT_KERN_FLAG(MNTK_DRAINING); 3659 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3660 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3661 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3662 MNT_KERN_FLAG(MNTK_NO_IOPF); 3663 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3664 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3665 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3666 MNT_KERN_FLAG(MNTK_MARKER); 3667 MNT_KERN_FLAG(MNTK_USES_BCACHE); 3668 MNT_KERN_FLAG(MNTK_NOASYNC); 3669 MNT_KERN_FLAG(MNTK_UNMOUNT); 3670 MNT_KERN_FLAG(MNTK_MWAIT); 3671 MNT_KERN_FLAG(MNTK_SUSPEND); 3672 MNT_KERN_FLAG(MNTK_SUSPEND2); 3673 MNT_KERN_FLAG(MNTK_SUSPENDED); 3674 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3675 MNT_KERN_FLAG(MNTK_NOKNOTE); 3676 #undef MNT_KERN_FLAG 3677 if (flags != 0) { 3678 if (buf[0] != '\0') 3679 strlcat(buf, ", ", sizeof(buf)); 3680 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3681 "0x%08x", flags); 3682 } 3683 db_printf(" mnt_kern_flag = %s\n", buf); 3684 3685 db_printf(" mnt_opt = "); 3686 opt = TAILQ_FIRST(mp->mnt_opt); 3687 if (opt != NULL) { 3688 db_printf("%s", opt->name); 3689 opt = TAILQ_NEXT(opt, link); 3690 while (opt != NULL) { 3691 db_printf(", %s", opt->name); 3692 opt = TAILQ_NEXT(opt, link); 3693 } 3694 } 3695 db_printf("\n"); 3696 3697 sp = &mp->mnt_stat; 3698 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3699 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3700 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3701 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3702 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3703 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3704 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3705 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3706 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3707 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3708 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3709 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3710 3711 db_printf(" mnt_cred = { uid=%u ruid=%u", 3712 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3713 if (jailed(mp->mnt_cred)) 3714 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3715 db_printf(" }\n"); 3716 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3717 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3718 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3719 db_printf(" mnt_activevnodelistsize = %d\n", 3720 mp->mnt_activevnodelistsize); 3721 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3722 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3723 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3724 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3725 db_printf(" mnt_lockref = %d\n", mp->mnt_lockref); 3726 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3727 db_printf(" mnt_secondary_accwrites = %d\n", 3728 mp->mnt_secondary_accwrites); 3729 db_printf(" mnt_gjprovider = %s\n", 3730 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3731 3732 db_printf("\n\nList of active vnodes\n"); 3733 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3734 if (vp->v_type != VMARKER) { 3735 vn_printf(vp, "vnode "); 3736 if (db_pager_quit) 3737 break; 3738 } 3739 } 3740 db_printf("\n\nList of inactive vnodes\n"); 3741 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3742 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3743 vn_printf(vp, "vnode "); 3744 if (db_pager_quit) 3745 break; 3746 } 3747 } 3748 } 3749 #endif /* DDB */ 3750 3751 /* 3752 * Fill in a struct xvfsconf based on a struct vfsconf. 3753 */ 3754 static int 3755 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3756 { 3757 struct xvfsconf xvfsp; 3758 3759 bzero(&xvfsp, sizeof(xvfsp)); 3760 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3761 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3762 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3763 xvfsp.vfc_flags = vfsp->vfc_flags; 3764 /* 3765 * These are unused in userland, we keep them 3766 * to not break binary compatibility. 3767 */ 3768 xvfsp.vfc_vfsops = NULL; 3769 xvfsp.vfc_next = NULL; 3770 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3771 } 3772 3773 #ifdef COMPAT_FREEBSD32 3774 struct xvfsconf32 { 3775 uint32_t vfc_vfsops; 3776 char vfc_name[MFSNAMELEN]; 3777 int32_t vfc_typenum; 3778 int32_t vfc_refcount; 3779 int32_t vfc_flags; 3780 uint32_t vfc_next; 3781 }; 3782 3783 static int 3784 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3785 { 3786 struct xvfsconf32 xvfsp; 3787 3788 bzero(&xvfsp, sizeof(xvfsp)); 3789 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3790 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3791 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3792 xvfsp.vfc_flags = vfsp->vfc_flags; 3793 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3794 } 3795 #endif 3796 3797 /* 3798 * Top level filesystem related information gathering. 3799 */ 3800 static int 3801 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3802 { 3803 struct vfsconf *vfsp; 3804 int error; 3805 3806 error = 0; 3807 vfsconf_slock(); 3808 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3809 #ifdef COMPAT_FREEBSD32 3810 if (req->flags & SCTL_MASK32) 3811 error = vfsconf2x32(req, vfsp); 3812 else 3813 #endif 3814 error = vfsconf2x(req, vfsp); 3815 if (error) 3816 break; 3817 } 3818 vfsconf_sunlock(); 3819 return (error); 3820 } 3821 3822 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD | 3823 CTLFLAG_MPSAFE, NULL, 0, sysctl_vfs_conflist, 3824 "S,xvfsconf", "List of all configured filesystems"); 3825 3826 #ifndef BURN_BRIDGES 3827 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3828 3829 static int 3830 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3831 { 3832 int *name = (int *)arg1 - 1; /* XXX */ 3833 u_int namelen = arg2 + 1; /* XXX */ 3834 struct vfsconf *vfsp; 3835 3836 log(LOG_WARNING, "userland calling deprecated sysctl, " 3837 "please rebuild world\n"); 3838 3839 #if 1 || defined(COMPAT_PRELITE2) 3840 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3841 if (namelen == 1) 3842 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3843 #endif 3844 3845 switch (name[1]) { 3846 case VFS_MAXTYPENUM: 3847 if (namelen != 2) 3848 return (ENOTDIR); 3849 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3850 case VFS_CONF: 3851 if (namelen != 3) 3852 return (ENOTDIR); /* overloaded */ 3853 vfsconf_slock(); 3854 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3855 if (vfsp->vfc_typenum == name[2]) 3856 break; 3857 } 3858 vfsconf_sunlock(); 3859 if (vfsp == NULL) 3860 return (EOPNOTSUPP); 3861 #ifdef COMPAT_FREEBSD32 3862 if (req->flags & SCTL_MASK32) 3863 return (vfsconf2x32(req, vfsp)); 3864 else 3865 #endif 3866 return (vfsconf2x(req, vfsp)); 3867 } 3868 return (EOPNOTSUPP); 3869 } 3870 3871 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP | 3872 CTLFLAG_MPSAFE, vfs_sysctl, 3873 "Generic filesystem"); 3874 3875 #if 1 || defined(COMPAT_PRELITE2) 3876 3877 static int 3878 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3879 { 3880 int error; 3881 struct vfsconf *vfsp; 3882 struct ovfsconf ovfs; 3883 3884 vfsconf_slock(); 3885 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3886 bzero(&ovfs, sizeof(ovfs)); 3887 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3888 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3889 ovfs.vfc_index = vfsp->vfc_typenum; 3890 ovfs.vfc_refcount = vfsp->vfc_refcount; 3891 ovfs.vfc_flags = vfsp->vfc_flags; 3892 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3893 if (error != 0) { 3894 vfsconf_sunlock(); 3895 return (error); 3896 } 3897 } 3898 vfsconf_sunlock(); 3899 return (0); 3900 } 3901 3902 #endif /* 1 || COMPAT_PRELITE2 */ 3903 #endif /* !BURN_BRIDGES */ 3904 3905 #define KINFO_VNODESLOP 10 3906 #ifdef notyet 3907 /* 3908 * Dump vnode list (via sysctl). 3909 */ 3910 /* ARGSUSED */ 3911 static int 3912 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3913 { 3914 struct xvnode *xvn; 3915 struct mount *mp; 3916 struct vnode *vp; 3917 int error, len, n; 3918 3919 /* 3920 * Stale numvnodes access is not fatal here. 3921 */ 3922 req->lock = 0; 3923 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3924 if (!req->oldptr) 3925 /* Make an estimate */ 3926 return (SYSCTL_OUT(req, 0, len)); 3927 3928 error = sysctl_wire_old_buffer(req, 0); 3929 if (error != 0) 3930 return (error); 3931 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3932 n = 0; 3933 mtx_lock(&mountlist_mtx); 3934 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3935 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3936 continue; 3937 MNT_ILOCK(mp); 3938 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3939 if (n == len) 3940 break; 3941 vref(vp); 3942 xvn[n].xv_size = sizeof *xvn; 3943 xvn[n].xv_vnode = vp; 3944 xvn[n].xv_id = 0; /* XXX compat */ 3945 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3946 XV_COPY(usecount); 3947 XV_COPY(writecount); 3948 XV_COPY(holdcnt); 3949 XV_COPY(mount); 3950 XV_COPY(numoutput); 3951 XV_COPY(type); 3952 #undef XV_COPY 3953 xvn[n].xv_flag = vp->v_vflag; 3954 3955 switch (vp->v_type) { 3956 case VREG: 3957 case VDIR: 3958 case VLNK: 3959 break; 3960 case VBLK: 3961 case VCHR: 3962 if (vp->v_rdev == NULL) { 3963 vrele(vp); 3964 continue; 3965 } 3966 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3967 break; 3968 case VSOCK: 3969 xvn[n].xv_socket = vp->v_socket; 3970 break; 3971 case VFIFO: 3972 xvn[n].xv_fifo = vp->v_fifoinfo; 3973 break; 3974 case VNON: 3975 case VBAD: 3976 default: 3977 /* shouldn't happen? */ 3978 vrele(vp); 3979 continue; 3980 } 3981 vrele(vp); 3982 ++n; 3983 } 3984 MNT_IUNLOCK(mp); 3985 mtx_lock(&mountlist_mtx); 3986 vfs_unbusy(mp); 3987 if (n == len) 3988 break; 3989 } 3990 mtx_unlock(&mountlist_mtx); 3991 3992 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3993 free(xvn, M_TEMP); 3994 return (error); 3995 } 3996 3997 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE | CTLFLAG_RD | 3998 CTLFLAG_MPSAFE, 0, 0, sysctl_vnode, "S,xvnode", 3999 ""); 4000 #endif 4001 4002 static void 4003 unmount_or_warn(struct mount *mp) 4004 { 4005 int error; 4006 4007 error = dounmount(mp, MNT_FORCE, curthread); 4008 if (error != 0) { 4009 printf("unmount of %s failed (", mp->mnt_stat.f_mntonname); 4010 if (error == EBUSY) 4011 printf("BUSY)\n"); 4012 else 4013 printf("%d)\n", error); 4014 } 4015 } 4016 4017 /* 4018 * Unmount all filesystems. The list is traversed in reverse order 4019 * of mounting to avoid dependencies. 4020 */ 4021 void 4022 vfs_unmountall(void) 4023 { 4024 struct mount *mp, *tmp; 4025 4026 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 4027 4028 /* 4029 * Since this only runs when rebooting, it is not interlocked. 4030 */ 4031 TAILQ_FOREACH_REVERSE_SAFE(mp, &mountlist, mntlist, mnt_list, tmp) { 4032 vfs_ref(mp); 4033 4034 /* 4035 * Forcibly unmounting "/dev" before "/" would prevent clean 4036 * unmount of the latter. 4037 */ 4038 if (mp == rootdevmp) 4039 continue; 4040 4041 unmount_or_warn(mp); 4042 } 4043 4044 if (rootdevmp != NULL) 4045 unmount_or_warn(rootdevmp); 4046 } 4047 4048 /* 4049 * perform msync on all vnodes under a mount point 4050 * the mount point must be locked. 4051 */ 4052 void 4053 vfs_msync(struct mount *mp, int flags) 4054 { 4055 struct vnode *vp, *mvp; 4056 struct vm_object *obj; 4057 4058 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 4059 4060 vnlru_return_batch(mp); 4061 4062 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 4063 obj = vp->v_object; 4064 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 4065 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 4066 if (!vget(vp, 4067 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 4068 curthread)) { 4069 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 4070 vput(vp); 4071 continue; 4072 } 4073 4074 obj = vp->v_object; 4075 if (obj != NULL) { 4076 VM_OBJECT_WLOCK(obj); 4077 vm_object_page_clean(obj, 0, 0, 4078 flags == MNT_WAIT ? 4079 OBJPC_SYNC : OBJPC_NOSYNC); 4080 VM_OBJECT_WUNLOCK(obj); 4081 } 4082 vput(vp); 4083 } 4084 } else 4085 VI_UNLOCK(vp); 4086 } 4087 } 4088 4089 static void 4090 destroy_vpollinfo_free(struct vpollinfo *vi) 4091 { 4092 4093 knlist_destroy(&vi->vpi_selinfo.si_note); 4094 mtx_destroy(&vi->vpi_lock); 4095 uma_zfree(vnodepoll_zone, vi); 4096 } 4097 4098 static void 4099 destroy_vpollinfo(struct vpollinfo *vi) 4100 { 4101 4102 knlist_clear(&vi->vpi_selinfo.si_note, 1); 4103 seldrain(&vi->vpi_selinfo); 4104 destroy_vpollinfo_free(vi); 4105 } 4106 4107 /* 4108 * Initialize per-vnode helper structure to hold poll-related state. 4109 */ 4110 void 4111 v_addpollinfo(struct vnode *vp) 4112 { 4113 struct vpollinfo *vi; 4114 4115 if (vp->v_pollinfo != NULL) 4116 return; 4117 vi = uma_zalloc(vnodepoll_zone, M_WAITOK | M_ZERO); 4118 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 4119 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 4120 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 4121 VI_LOCK(vp); 4122 if (vp->v_pollinfo != NULL) { 4123 VI_UNLOCK(vp); 4124 destroy_vpollinfo_free(vi); 4125 return; 4126 } 4127 vp->v_pollinfo = vi; 4128 VI_UNLOCK(vp); 4129 } 4130 4131 /* 4132 * Record a process's interest in events which might happen to 4133 * a vnode. Because poll uses the historic select-style interface 4134 * internally, this routine serves as both the ``check for any 4135 * pending events'' and the ``record my interest in future events'' 4136 * functions. (These are done together, while the lock is held, 4137 * to avoid race conditions.) 4138 */ 4139 int 4140 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 4141 { 4142 4143 v_addpollinfo(vp); 4144 mtx_lock(&vp->v_pollinfo->vpi_lock); 4145 if (vp->v_pollinfo->vpi_revents & events) { 4146 /* 4147 * This leaves events we are not interested 4148 * in available for the other process which 4149 * which presumably had requested them 4150 * (otherwise they would never have been 4151 * recorded). 4152 */ 4153 events &= vp->v_pollinfo->vpi_revents; 4154 vp->v_pollinfo->vpi_revents &= ~events; 4155 4156 mtx_unlock(&vp->v_pollinfo->vpi_lock); 4157 return (events); 4158 } 4159 vp->v_pollinfo->vpi_events |= events; 4160 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 4161 mtx_unlock(&vp->v_pollinfo->vpi_lock); 4162 return (0); 4163 } 4164 4165 /* 4166 * Routine to create and manage a filesystem syncer vnode. 4167 */ 4168 #define sync_close ((int (*)(struct vop_close_args *))nullop) 4169 static int sync_fsync(struct vop_fsync_args *); 4170 static int sync_inactive(struct vop_inactive_args *); 4171 static int sync_reclaim(struct vop_reclaim_args *); 4172 4173 static struct vop_vector sync_vnodeops = { 4174 .vop_bypass = VOP_EOPNOTSUPP, 4175 .vop_close = sync_close, /* close */ 4176 .vop_fsync = sync_fsync, /* fsync */ 4177 .vop_inactive = sync_inactive, /* inactive */ 4178 .vop_reclaim = sync_reclaim, /* reclaim */ 4179 .vop_lock1 = vop_stdlock, /* lock */ 4180 .vop_unlock = vop_stdunlock, /* unlock */ 4181 .vop_islocked = vop_stdislocked, /* islocked */ 4182 }; 4183 4184 /* 4185 * Create a new filesystem syncer vnode for the specified mount point. 4186 */ 4187 void 4188 vfs_allocate_syncvnode(struct mount *mp) 4189 { 4190 struct vnode *vp; 4191 struct bufobj *bo; 4192 static long start, incr, next; 4193 int error; 4194 4195 /* Allocate a new vnode */ 4196 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 4197 if (error != 0) 4198 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 4199 vp->v_type = VNON; 4200 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4201 vp->v_vflag |= VV_FORCEINSMQ; 4202 error = insmntque(vp, mp); 4203 if (error != 0) 4204 panic("vfs_allocate_syncvnode: insmntque() failed"); 4205 vp->v_vflag &= ~VV_FORCEINSMQ; 4206 VOP_UNLOCK(vp, 0); 4207 /* 4208 * Place the vnode onto the syncer worklist. We attempt to 4209 * scatter them about on the list so that they will go off 4210 * at evenly distributed times even if all the filesystems 4211 * are mounted at once. 4212 */ 4213 next += incr; 4214 if (next == 0 || next > syncer_maxdelay) { 4215 start /= 2; 4216 incr /= 2; 4217 if (start == 0) { 4218 start = syncer_maxdelay / 2; 4219 incr = syncer_maxdelay; 4220 } 4221 next = start; 4222 } 4223 bo = &vp->v_bufobj; 4224 BO_LOCK(bo); 4225 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 4226 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 4227 mtx_lock(&sync_mtx); 4228 sync_vnode_count++; 4229 if (mp->mnt_syncer == NULL) { 4230 mp->mnt_syncer = vp; 4231 vp = NULL; 4232 } 4233 mtx_unlock(&sync_mtx); 4234 BO_UNLOCK(bo); 4235 if (vp != NULL) { 4236 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4237 vgone(vp); 4238 vput(vp); 4239 } 4240 } 4241 4242 void 4243 vfs_deallocate_syncvnode(struct mount *mp) 4244 { 4245 struct vnode *vp; 4246 4247 mtx_lock(&sync_mtx); 4248 vp = mp->mnt_syncer; 4249 if (vp != NULL) 4250 mp->mnt_syncer = NULL; 4251 mtx_unlock(&sync_mtx); 4252 if (vp != NULL) 4253 vrele(vp); 4254 } 4255 4256 /* 4257 * Do a lazy sync of the filesystem. 4258 */ 4259 static int 4260 sync_fsync(struct vop_fsync_args *ap) 4261 { 4262 struct vnode *syncvp = ap->a_vp; 4263 struct mount *mp = syncvp->v_mount; 4264 int error, save; 4265 struct bufobj *bo; 4266 4267 /* 4268 * We only need to do something if this is a lazy evaluation. 4269 */ 4270 if (ap->a_waitfor != MNT_LAZY) 4271 return (0); 4272 4273 /* 4274 * Move ourselves to the back of the sync list. 4275 */ 4276 bo = &syncvp->v_bufobj; 4277 BO_LOCK(bo); 4278 vn_syncer_add_to_worklist(bo, syncdelay); 4279 BO_UNLOCK(bo); 4280 4281 /* 4282 * Walk the list of vnodes pushing all that are dirty and 4283 * not already on the sync list. 4284 */ 4285 if (vfs_busy(mp, MBF_NOWAIT) != 0) 4286 return (0); 4287 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 4288 vfs_unbusy(mp); 4289 return (0); 4290 } 4291 save = curthread_pflags_set(TDP_SYNCIO); 4292 vfs_msync(mp, MNT_NOWAIT); 4293 error = VFS_SYNC(mp, MNT_LAZY); 4294 curthread_pflags_restore(save); 4295 vn_finished_write(mp); 4296 vfs_unbusy(mp); 4297 return (error); 4298 } 4299 4300 /* 4301 * The syncer vnode is no referenced. 4302 */ 4303 static int 4304 sync_inactive(struct vop_inactive_args *ap) 4305 { 4306 4307 vgone(ap->a_vp); 4308 return (0); 4309 } 4310 4311 /* 4312 * The syncer vnode is no longer needed and is being decommissioned. 4313 * 4314 * Modifications to the worklist must be protected by sync_mtx. 4315 */ 4316 static int 4317 sync_reclaim(struct vop_reclaim_args *ap) 4318 { 4319 struct vnode *vp = ap->a_vp; 4320 struct bufobj *bo; 4321 4322 bo = &vp->v_bufobj; 4323 BO_LOCK(bo); 4324 mtx_lock(&sync_mtx); 4325 if (vp->v_mount->mnt_syncer == vp) 4326 vp->v_mount->mnt_syncer = NULL; 4327 if (bo->bo_flag & BO_ONWORKLST) { 4328 LIST_REMOVE(bo, bo_synclist); 4329 syncer_worklist_len--; 4330 sync_vnode_count--; 4331 bo->bo_flag &= ~BO_ONWORKLST; 4332 } 4333 mtx_unlock(&sync_mtx); 4334 BO_UNLOCK(bo); 4335 4336 return (0); 4337 } 4338 4339 /* 4340 * Check if vnode represents a disk device 4341 */ 4342 int 4343 vn_isdisk(struct vnode *vp, int *errp) 4344 { 4345 int error; 4346 4347 if (vp->v_type != VCHR) { 4348 error = ENOTBLK; 4349 goto out; 4350 } 4351 error = 0; 4352 dev_lock(); 4353 if (vp->v_rdev == NULL) 4354 error = ENXIO; 4355 else if (vp->v_rdev->si_devsw == NULL) 4356 error = ENXIO; 4357 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 4358 error = ENOTBLK; 4359 dev_unlock(); 4360 out: 4361 if (errp != NULL) 4362 *errp = error; 4363 return (error == 0); 4364 } 4365 4366 /* 4367 * Common filesystem object access control check routine. Accepts a 4368 * vnode's type, "mode", uid and gid, requested access mode, credentials, 4369 * and optional call-by-reference privused argument allowing vaccess() 4370 * to indicate to the caller whether privilege was used to satisfy the 4371 * request (obsoleted). Returns 0 on success, or an errno on failure. 4372 */ 4373 int 4374 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 4375 accmode_t accmode, struct ucred *cred, int *privused) 4376 { 4377 accmode_t dac_granted; 4378 accmode_t priv_granted; 4379 4380 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 4381 ("invalid bit in accmode")); 4382 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 4383 ("VAPPEND without VWRITE")); 4384 4385 /* 4386 * Look for a normal, non-privileged way to access the file/directory 4387 * as requested. If it exists, go with that. 4388 */ 4389 4390 if (privused != NULL) 4391 *privused = 0; 4392 4393 dac_granted = 0; 4394 4395 /* Check the owner. */ 4396 if (cred->cr_uid == file_uid) { 4397 dac_granted |= VADMIN; 4398 if (file_mode & S_IXUSR) 4399 dac_granted |= VEXEC; 4400 if (file_mode & S_IRUSR) 4401 dac_granted |= VREAD; 4402 if (file_mode & S_IWUSR) 4403 dac_granted |= (VWRITE | VAPPEND); 4404 4405 if ((accmode & dac_granted) == accmode) 4406 return (0); 4407 4408 goto privcheck; 4409 } 4410 4411 /* Otherwise, check the groups (first match) */ 4412 if (groupmember(file_gid, cred)) { 4413 if (file_mode & S_IXGRP) 4414 dac_granted |= VEXEC; 4415 if (file_mode & S_IRGRP) 4416 dac_granted |= VREAD; 4417 if (file_mode & S_IWGRP) 4418 dac_granted |= (VWRITE | VAPPEND); 4419 4420 if ((accmode & dac_granted) == accmode) 4421 return (0); 4422 4423 goto privcheck; 4424 } 4425 4426 /* Otherwise, check everyone else. */ 4427 if (file_mode & S_IXOTH) 4428 dac_granted |= VEXEC; 4429 if (file_mode & S_IROTH) 4430 dac_granted |= VREAD; 4431 if (file_mode & S_IWOTH) 4432 dac_granted |= (VWRITE | VAPPEND); 4433 if ((accmode & dac_granted) == accmode) 4434 return (0); 4435 4436 privcheck: 4437 /* 4438 * Build a privilege mask to determine if the set of privileges 4439 * satisfies the requirements when combined with the granted mask 4440 * from above. For each privilege, if the privilege is required, 4441 * bitwise or the request type onto the priv_granted mask. 4442 */ 4443 priv_granted = 0; 4444 4445 if (type == VDIR) { 4446 /* 4447 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 4448 * requests, instead of PRIV_VFS_EXEC. 4449 */ 4450 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 4451 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 4452 priv_granted |= VEXEC; 4453 } else { 4454 /* 4455 * Ensure that at least one execute bit is on. Otherwise, 4456 * a privileged user will always succeed, and we don't want 4457 * this to happen unless the file really is executable. 4458 */ 4459 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 4460 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 4461 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 4462 priv_granted |= VEXEC; 4463 } 4464 4465 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 4466 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 4467 priv_granted |= VREAD; 4468 4469 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 4470 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 4471 priv_granted |= (VWRITE | VAPPEND); 4472 4473 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 4474 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 4475 priv_granted |= VADMIN; 4476 4477 if ((accmode & (priv_granted | dac_granted)) == accmode) { 4478 /* XXX audit: privilege used */ 4479 if (privused != NULL) 4480 *privused = 1; 4481 return (0); 4482 } 4483 4484 return ((accmode & VADMIN) ? EPERM : EACCES); 4485 } 4486 4487 /* 4488 * Credential check based on process requesting service, and per-attribute 4489 * permissions. 4490 */ 4491 int 4492 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 4493 struct thread *td, accmode_t accmode) 4494 { 4495 4496 /* 4497 * Kernel-invoked always succeeds. 4498 */ 4499 if (cred == NOCRED) 4500 return (0); 4501 4502 /* 4503 * Do not allow privileged processes in jail to directly manipulate 4504 * system attributes. 4505 */ 4506 switch (attrnamespace) { 4507 case EXTATTR_NAMESPACE_SYSTEM: 4508 /* Potentially should be: return (EPERM); */ 4509 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 4510 case EXTATTR_NAMESPACE_USER: 4511 return (VOP_ACCESS(vp, accmode, cred, td)); 4512 default: 4513 return (EPERM); 4514 } 4515 } 4516 4517 #ifdef DEBUG_VFS_LOCKS 4518 /* 4519 * This only exists to suppress warnings from unlocked specfs accesses. It is 4520 * no longer ok to have an unlocked VFS. 4521 */ 4522 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 4523 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 4524 4525 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 4526 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 4527 "Drop into debugger on lock violation"); 4528 4529 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 4530 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 4531 0, "Check for interlock across VOPs"); 4532 4533 int vfs_badlock_print = 1; /* Print lock violations. */ 4534 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 4535 0, "Print lock violations"); 4536 4537 int vfs_badlock_vnode = 1; /* Print vnode details on lock violations. */ 4538 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_vnode, CTLFLAG_RW, &vfs_badlock_vnode, 4539 0, "Print vnode details on lock violations"); 4540 4541 #ifdef KDB 4542 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 4543 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 4544 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 4545 #endif 4546 4547 static void 4548 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 4549 { 4550 4551 #ifdef KDB 4552 if (vfs_badlock_backtrace) 4553 kdb_backtrace(); 4554 #endif 4555 if (vfs_badlock_vnode) 4556 vn_printf(vp, "vnode "); 4557 if (vfs_badlock_print) 4558 printf("%s: %p %s\n", str, (void *)vp, msg); 4559 if (vfs_badlock_ddb) 4560 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4561 } 4562 4563 void 4564 assert_vi_locked(struct vnode *vp, const char *str) 4565 { 4566 4567 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 4568 vfs_badlock("interlock is not locked but should be", str, vp); 4569 } 4570 4571 void 4572 assert_vi_unlocked(struct vnode *vp, const char *str) 4573 { 4574 4575 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 4576 vfs_badlock("interlock is locked but should not be", str, vp); 4577 } 4578 4579 void 4580 assert_vop_locked(struct vnode *vp, const char *str) 4581 { 4582 int locked; 4583 4584 if (!IGNORE_LOCK(vp)) { 4585 locked = VOP_ISLOCKED(vp); 4586 if (locked == 0 || locked == LK_EXCLOTHER) 4587 vfs_badlock("is not locked but should be", str, vp); 4588 } 4589 } 4590 4591 void 4592 assert_vop_unlocked(struct vnode *vp, const char *str) 4593 { 4594 4595 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 4596 vfs_badlock("is locked but should not be", str, vp); 4597 } 4598 4599 void 4600 assert_vop_elocked(struct vnode *vp, const char *str) 4601 { 4602 4603 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 4604 vfs_badlock("is not exclusive locked but should be", str, vp); 4605 } 4606 #endif /* DEBUG_VFS_LOCKS */ 4607 4608 void 4609 vop_rename_fail(struct vop_rename_args *ap) 4610 { 4611 4612 if (ap->a_tvp != NULL) 4613 vput(ap->a_tvp); 4614 if (ap->a_tdvp == ap->a_tvp) 4615 vrele(ap->a_tdvp); 4616 else 4617 vput(ap->a_tdvp); 4618 vrele(ap->a_fdvp); 4619 vrele(ap->a_fvp); 4620 } 4621 4622 void 4623 vop_rename_pre(void *ap) 4624 { 4625 struct vop_rename_args *a = ap; 4626 4627 #ifdef DEBUG_VFS_LOCKS 4628 if (a->a_tvp) 4629 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4630 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4631 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4632 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4633 4634 /* Check the source (from). */ 4635 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4636 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4637 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4638 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4639 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4640 4641 /* Check the target. */ 4642 if (a->a_tvp) 4643 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4644 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4645 #endif 4646 if (a->a_tdvp != a->a_fdvp) 4647 vhold(a->a_fdvp); 4648 if (a->a_tvp != a->a_fvp) 4649 vhold(a->a_fvp); 4650 vhold(a->a_tdvp); 4651 if (a->a_tvp) 4652 vhold(a->a_tvp); 4653 } 4654 4655 #ifdef DEBUG_VFS_LOCKS 4656 void 4657 vop_strategy_pre(void *ap) 4658 { 4659 struct vop_strategy_args *a; 4660 struct buf *bp; 4661 4662 a = ap; 4663 bp = a->a_bp; 4664 4665 /* 4666 * Cluster ops lock their component buffers but not the IO container. 4667 */ 4668 if ((bp->b_flags & B_CLUSTER) != 0) 4669 return; 4670 4671 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4672 if (vfs_badlock_print) 4673 printf( 4674 "VOP_STRATEGY: bp is not locked but should be\n"); 4675 if (vfs_badlock_ddb) 4676 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4677 } 4678 } 4679 4680 void 4681 vop_lock_pre(void *ap) 4682 { 4683 struct vop_lock1_args *a = ap; 4684 4685 if ((a->a_flags & LK_INTERLOCK) == 0) 4686 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4687 else 4688 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4689 } 4690 4691 void 4692 vop_lock_post(void *ap, int rc) 4693 { 4694 struct vop_lock1_args *a = ap; 4695 4696 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4697 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4698 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4699 } 4700 4701 void 4702 vop_unlock_pre(void *ap) 4703 { 4704 struct vop_unlock_args *a = ap; 4705 4706 if (a->a_flags & LK_INTERLOCK) 4707 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4708 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4709 } 4710 4711 void 4712 vop_unlock_post(void *ap, int rc) 4713 { 4714 struct vop_unlock_args *a = ap; 4715 4716 if (a->a_flags & LK_INTERLOCK) 4717 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4718 } 4719 #endif 4720 4721 void 4722 vop_create_post(void *ap, int rc) 4723 { 4724 struct vop_create_args *a = ap; 4725 4726 if (!rc) 4727 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4728 } 4729 4730 void 4731 vop_deleteextattr_post(void *ap, int rc) 4732 { 4733 struct vop_deleteextattr_args *a = ap; 4734 4735 if (!rc) 4736 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4737 } 4738 4739 void 4740 vop_link_post(void *ap, int rc) 4741 { 4742 struct vop_link_args *a = ap; 4743 4744 if (!rc) { 4745 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4746 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4747 } 4748 } 4749 4750 void 4751 vop_mkdir_post(void *ap, int rc) 4752 { 4753 struct vop_mkdir_args *a = ap; 4754 4755 if (!rc) 4756 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4757 } 4758 4759 void 4760 vop_mknod_post(void *ap, int rc) 4761 { 4762 struct vop_mknod_args *a = ap; 4763 4764 if (!rc) 4765 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4766 } 4767 4768 void 4769 vop_reclaim_post(void *ap, int rc) 4770 { 4771 struct vop_reclaim_args *a = ap; 4772 4773 if (!rc) 4774 VFS_KNOTE_LOCKED(a->a_vp, NOTE_REVOKE); 4775 } 4776 4777 void 4778 vop_remove_post(void *ap, int rc) 4779 { 4780 struct vop_remove_args *a = ap; 4781 4782 if (!rc) { 4783 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4784 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4785 } 4786 } 4787 4788 void 4789 vop_rename_post(void *ap, int rc) 4790 { 4791 struct vop_rename_args *a = ap; 4792 long hint; 4793 4794 if (!rc) { 4795 hint = NOTE_WRITE; 4796 if (a->a_fdvp == a->a_tdvp) { 4797 if (a->a_tvp != NULL && a->a_tvp->v_type == VDIR) 4798 hint |= NOTE_LINK; 4799 VFS_KNOTE_UNLOCKED(a->a_fdvp, hint); 4800 VFS_KNOTE_UNLOCKED(a->a_tdvp, hint); 4801 } else { 4802 hint |= NOTE_EXTEND; 4803 if (a->a_fvp->v_type == VDIR) 4804 hint |= NOTE_LINK; 4805 VFS_KNOTE_UNLOCKED(a->a_fdvp, hint); 4806 4807 if (a->a_fvp->v_type == VDIR && a->a_tvp != NULL && 4808 a->a_tvp->v_type == VDIR) 4809 hint &= ~NOTE_LINK; 4810 VFS_KNOTE_UNLOCKED(a->a_tdvp, hint); 4811 } 4812 4813 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4814 if (a->a_tvp) 4815 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4816 } 4817 if (a->a_tdvp != a->a_fdvp) 4818 vdrop(a->a_fdvp); 4819 if (a->a_tvp != a->a_fvp) 4820 vdrop(a->a_fvp); 4821 vdrop(a->a_tdvp); 4822 if (a->a_tvp) 4823 vdrop(a->a_tvp); 4824 } 4825 4826 void 4827 vop_rmdir_post(void *ap, int rc) 4828 { 4829 struct vop_rmdir_args *a = ap; 4830 4831 if (!rc) { 4832 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4833 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4834 } 4835 } 4836 4837 void 4838 vop_setattr_post(void *ap, int rc) 4839 { 4840 struct vop_setattr_args *a = ap; 4841 4842 if (!rc) 4843 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4844 } 4845 4846 void 4847 vop_setextattr_post(void *ap, int rc) 4848 { 4849 struct vop_setextattr_args *a = ap; 4850 4851 if (!rc) 4852 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4853 } 4854 4855 void 4856 vop_symlink_post(void *ap, int rc) 4857 { 4858 struct vop_symlink_args *a = ap; 4859 4860 if (!rc) 4861 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4862 } 4863 4864 void 4865 vop_open_post(void *ap, int rc) 4866 { 4867 struct vop_open_args *a = ap; 4868 4869 if (!rc) 4870 VFS_KNOTE_LOCKED(a->a_vp, NOTE_OPEN); 4871 } 4872 4873 void 4874 vop_close_post(void *ap, int rc) 4875 { 4876 struct vop_close_args *a = ap; 4877 4878 if (!rc && (a->a_cred != NOCRED || /* filter out revokes */ 4879 (a->a_vp->v_iflag & VI_DOOMED) == 0)) { 4880 VFS_KNOTE_LOCKED(a->a_vp, (a->a_fflag & FWRITE) != 0 ? 4881 NOTE_CLOSE_WRITE : NOTE_CLOSE); 4882 } 4883 } 4884 4885 void 4886 vop_read_post(void *ap, int rc) 4887 { 4888 struct vop_read_args *a = ap; 4889 4890 if (!rc) 4891 VFS_KNOTE_LOCKED(a->a_vp, NOTE_READ); 4892 } 4893 4894 void 4895 vop_readdir_post(void *ap, int rc) 4896 { 4897 struct vop_readdir_args *a = ap; 4898 4899 if (!rc) 4900 VFS_KNOTE_LOCKED(a->a_vp, NOTE_READ); 4901 } 4902 4903 static struct knlist fs_knlist; 4904 4905 static void 4906 vfs_event_init(void *arg) 4907 { 4908 knlist_init_mtx(&fs_knlist, NULL); 4909 } 4910 /* XXX - correct order? */ 4911 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4912 4913 void 4914 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4915 { 4916 4917 KNOTE_UNLOCKED(&fs_knlist, event); 4918 } 4919 4920 static int filt_fsattach(struct knote *kn); 4921 static void filt_fsdetach(struct knote *kn); 4922 static int filt_fsevent(struct knote *kn, long hint); 4923 4924 struct filterops fs_filtops = { 4925 .f_isfd = 0, 4926 .f_attach = filt_fsattach, 4927 .f_detach = filt_fsdetach, 4928 .f_event = filt_fsevent 4929 }; 4930 4931 static int 4932 filt_fsattach(struct knote *kn) 4933 { 4934 4935 kn->kn_flags |= EV_CLEAR; 4936 knlist_add(&fs_knlist, kn, 0); 4937 return (0); 4938 } 4939 4940 static void 4941 filt_fsdetach(struct knote *kn) 4942 { 4943 4944 knlist_remove(&fs_knlist, kn, 0); 4945 } 4946 4947 static int 4948 filt_fsevent(struct knote *kn, long hint) 4949 { 4950 4951 kn->kn_fflags |= hint; 4952 return (kn->kn_fflags != 0); 4953 } 4954 4955 static int 4956 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4957 { 4958 struct vfsidctl vc; 4959 int error; 4960 struct mount *mp; 4961 4962 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4963 if (error) 4964 return (error); 4965 if (vc.vc_vers != VFS_CTL_VERS1) 4966 return (EINVAL); 4967 mp = vfs_getvfs(&vc.vc_fsid); 4968 if (mp == NULL) 4969 return (ENOENT); 4970 /* ensure that a specific sysctl goes to the right filesystem. */ 4971 if (strcmp(vc.vc_fstypename, "*") != 0 && 4972 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4973 vfs_rel(mp); 4974 return (EINVAL); 4975 } 4976 VCTLTOREQ(&vc, req); 4977 error = VFS_SYSCTL(mp, vc.vc_op, req); 4978 vfs_rel(mp); 4979 return (error); 4980 } 4981 4982 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4983 NULL, 0, sysctl_vfs_ctl, "", 4984 "Sysctl by fsid"); 4985 4986 /* 4987 * Function to initialize a va_filerev field sensibly. 4988 * XXX: Wouldn't a random number make a lot more sense ?? 4989 */ 4990 u_quad_t 4991 init_va_filerev(void) 4992 { 4993 struct bintime bt; 4994 4995 getbinuptime(&bt); 4996 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4997 } 4998 4999 static int filt_vfsread(struct knote *kn, long hint); 5000 static int filt_vfswrite(struct knote *kn, long hint); 5001 static int filt_vfsvnode(struct knote *kn, long hint); 5002 static void filt_vfsdetach(struct knote *kn); 5003 static struct filterops vfsread_filtops = { 5004 .f_isfd = 1, 5005 .f_detach = filt_vfsdetach, 5006 .f_event = filt_vfsread 5007 }; 5008 static struct filterops vfswrite_filtops = { 5009 .f_isfd = 1, 5010 .f_detach = filt_vfsdetach, 5011 .f_event = filt_vfswrite 5012 }; 5013 static struct filterops vfsvnode_filtops = { 5014 .f_isfd = 1, 5015 .f_detach = filt_vfsdetach, 5016 .f_event = filt_vfsvnode 5017 }; 5018 5019 static void 5020 vfs_knllock(void *arg) 5021 { 5022 struct vnode *vp = arg; 5023 5024 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 5025 } 5026 5027 static void 5028 vfs_knlunlock(void *arg) 5029 { 5030 struct vnode *vp = arg; 5031 5032 VOP_UNLOCK(vp, 0); 5033 } 5034 5035 static void 5036 vfs_knl_assert_locked(void *arg) 5037 { 5038 #ifdef DEBUG_VFS_LOCKS 5039 struct vnode *vp = arg; 5040 5041 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 5042 #endif 5043 } 5044 5045 static void 5046 vfs_knl_assert_unlocked(void *arg) 5047 { 5048 #ifdef DEBUG_VFS_LOCKS 5049 struct vnode *vp = arg; 5050 5051 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 5052 #endif 5053 } 5054 5055 int 5056 vfs_kqfilter(struct vop_kqfilter_args *ap) 5057 { 5058 struct vnode *vp = ap->a_vp; 5059 struct knote *kn = ap->a_kn; 5060 struct knlist *knl; 5061 5062 switch (kn->kn_filter) { 5063 case EVFILT_READ: 5064 kn->kn_fop = &vfsread_filtops; 5065 break; 5066 case EVFILT_WRITE: 5067 kn->kn_fop = &vfswrite_filtops; 5068 break; 5069 case EVFILT_VNODE: 5070 kn->kn_fop = &vfsvnode_filtops; 5071 break; 5072 default: 5073 return (EINVAL); 5074 } 5075 5076 kn->kn_hook = (caddr_t)vp; 5077 5078 v_addpollinfo(vp); 5079 if (vp->v_pollinfo == NULL) 5080 return (ENOMEM); 5081 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 5082 vhold(vp); 5083 knlist_add(knl, kn, 0); 5084 5085 return (0); 5086 } 5087 5088 /* 5089 * Detach knote from vnode 5090 */ 5091 static void 5092 filt_vfsdetach(struct knote *kn) 5093 { 5094 struct vnode *vp = (struct vnode *)kn->kn_hook; 5095 5096 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 5097 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 5098 vdrop(vp); 5099 } 5100 5101 /*ARGSUSED*/ 5102 static int 5103 filt_vfsread(struct knote *kn, long hint) 5104 { 5105 struct vnode *vp = (struct vnode *)kn->kn_hook; 5106 struct vattr va; 5107 int res; 5108 5109 /* 5110 * filesystem is gone, so set the EOF flag and schedule 5111 * the knote for deletion. 5112 */ 5113 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) { 5114 VI_LOCK(vp); 5115 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 5116 VI_UNLOCK(vp); 5117 return (1); 5118 } 5119 5120 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 5121 return (0); 5122 5123 VI_LOCK(vp); 5124 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 5125 res = (kn->kn_sfflags & NOTE_FILE_POLL) != 0 || kn->kn_data != 0; 5126 VI_UNLOCK(vp); 5127 return (res); 5128 } 5129 5130 /*ARGSUSED*/ 5131 static int 5132 filt_vfswrite(struct knote *kn, long hint) 5133 { 5134 struct vnode *vp = (struct vnode *)kn->kn_hook; 5135 5136 VI_LOCK(vp); 5137 5138 /* 5139 * filesystem is gone, so set the EOF flag and schedule 5140 * the knote for deletion. 5141 */ 5142 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) 5143 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 5144 5145 kn->kn_data = 0; 5146 VI_UNLOCK(vp); 5147 return (1); 5148 } 5149 5150 static int 5151 filt_vfsvnode(struct knote *kn, long hint) 5152 { 5153 struct vnode *vp = (struct vnode *)kn->kn_hook; 5154 int res; 5155 5156 VI_LOCK(vp); 5157 if (kn->kn_sfflags & hint) 5158 kn->kn_fflags |= hint; 5159 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) { 5160 kn->kn_flags |= EV_EOF; 5161 VI_UNLOCK(vp); 5162 return (1); 5163 } 5164 res = (kn->kn_fflags != 0); 5165 VI_UNLOCK(vp); 5166 return (res); 5167 } 5168 5169 int 5170 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 5171 { 5172 int error; 5173 5174 if (dp->d_reclen > ap->a_uio->uio_resid) 5175 return (ENAMETOOLONG); 5176 error = uiomove(dp, dp->d_reclen, ap->a_uio); 5177 if (error) { 5178 if (ap->a_ncookies != NULL) { 5179 if (ap->a_cookies != NULL) 5180 free(ap->a_cookies, M_TEMP); 5181 ap->a_cookies = NULL; 5182 *ap->a_ncookies = 0; 5183 } 5184 return (error); 5185 } 5186 if (ap->a_ncookies == NULL) 5187 return (0); 5188 5189 KASSERT(ap->a_cookies, 5190 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 5191 5192 *ap->a_cookies = realloc(*ap->a_cookies, 5193 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 5194 (*ap->a_cookies)[*ap->a_ncookies] = off; 5195 *ap->a_ncookies += 1; 5196 return (0); 5197 } 5198 5199 /* 5200 * Mark for update the access time of the file if the filesystem 5201 * supports VOP_MARKATIME. This functionality is used by execve and 5202 * mmap, so we want to avoid the I/O implied by directly setting 5203 * va_atime for the sake of efficiency. 5204 */ 5205 void 5206 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 5207 { 5208 struct mount *mp; 5209 5210 mp = vp->v_mount; 5211 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 5212 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 5213 (void)VOP_MARKATIME(vp); 5214 } 5215 5216 /* 5217 * The purpose of this routine is to remove granularity from accmode_t, 5218 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 5219 * VADMIN and VAPPEND. 5220 * 5221 * If it returns 0, the caller is supposed to continue with the usual 5222 * access checks using 'accmode' as modified by this routine. If it 5223 * returns nonzero value, the caller is supposed to return that value 5224 * as errno. 5225 * 5226 * Note that after this routine runs, accmode may be zero. 5227 */ 5228 int 5229 vfs_unixify_accmode(accmode_t *accmode) 5230 { 5231 /* 5232 * There is no way to specify explicit "deny" rule using 5233 * file mode or POSIX.1e ACLs. 5234 */ 5235 if (*accmode & VEXPLICIT_DENY) { 5236 *accmode = 0; 5237 return (0); 5238 } 5239 5240 /* 5241 * None of these can be translated into usual access bits. 5242 * Also, the common case for NFSv4 ACLs is to not contain 5243 * either of these bits. Caller should check for VWRITE 5244 * on the containing directory instead. 5245 */ 5246 if (*accmode & (VDELETE_CHILD | VDELETE)) 5247 return (EPERM); 5248 5249 if (*accmode & VADMIN_PERMS) { 5250 *accmode &= ~VADMIN_PERMS; 5251 *accmode |= VADMIN; 5252 } 5253 5254 /* 5255 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 5256 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 5257 */ 5258 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 5259 5260 return (0); 5261 } 5262 5263 /* 5264 * These are helper functions for filesystems to traverse all 5265 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 5266 * 5267 * This interface replaces MNT_VNODE_FOREACH. 5268 */ 5269 5270 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 5271 5272 struct vnode * 5273 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 5274 { 5275 struct vnode *vp; 5276 5277 if (should_yield()) 5278 kern_yield(PRI_USER); 5279 MNT_ILOCK(mp); 5280 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5281 for (vp = TAILQ_NEXT(*mvp, v_nmntvnodes); vp != NULL; 5282 vp = TAILQ_NEXT(vp, v_nmntvnodes)) { 5283 /* Allow a racy peek at VI_DOOMED to save a lock acquisition. */ 5284 if (vp->v_type == VMARKER || (vp->v_iflag & VI_DOOMED) != 0) 5285 continue; 5286 VI_LOCK(vp); 5287 if ((vp->v_iflag & VI_DOOMED) != 0) { 5288 VI_UNLOCK(vp); 5289 continue; 5290 } 5291 break; 5292 } 5293 if (vp == NULL) { 5294 __mnt_vnode_markerfree_all(mvp, mp); 5295 /* MNT_IUNLOCK(mp); -- done in above function */ 5296 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 5297 return (NULL); 5298 } 5299 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 5300 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 5301 MNT_IUNLOCK(mp); 5302 return (vp); 5303 } 5304 5305 struct vnode * 5306 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 5307 { 5308 struct vnode *vp; 5309 5310 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 5311 MNT_ILOCK(mp); 5312 MNT_REF(mp); 5313 (*mvp)->v_mount = mp; 5314 (*mvp)->v_type = VMARKER; 5315 5316 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 5317 /* Allow a racy peek at VI_DOOMED to save a lock acquisition. */ 5318 if (vp->v_type == VMARKER || (vp->v_iflag & VI_DOOMED) != 0) 5319 continue; 5320 VI_LOCK(vp); 5321 if ((vp->v_iflag & VI_DOOMED) != 0) { 5322 VI_UNLOCK(vp); 5323 continue; 5324 } 5325 break; 5326 } 5327 if (vp == NULL) { 5328 MNT_REL(mp); 5329 MNT_IUNLOCK(mp); 5330 free(*mvp, M_VNODE_MARKER); 5331 *mvp = NULL; 5332 return (NULL); 5333 } 5334 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 5335 MNT_IUNLOCK(mp); 5336 return (vp); 5337 } 5338 5339 void 5340 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 5341 { 5342 5343 if (*mvp == NULL) { 5344 MNT_IUNLOCK(mp); 5345 return; 5346 } 5347 5348 mtx_assert(MNT_MTX(mp), MA_OWNED); 5349 5350 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5351 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 5352 MNT_REL(mp); 5353 MNT_IUNLOCK(mp); 5354 free(*mvp, M_VNODE_MARKER); 5355 *mvp = NULL; 5356 } 5357 5358 /* 5359 * These are helper functions for filesystems to traverse their 5360 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 5361 */ 5362 static void 5363 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 5364 { 5365 5366 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5367 5368 MNT_ILOCK(mp); 5369 MNT_REL(mp); 5370 MNT_IUNLOCK(mp); 5371 free(*mvp, M_VNODE_MARKER); 5372 *mvp = NULL; 5373 } 5374 5375 /* 5376 * Relock the mp mount vnode list lock with the vp vnode interlock in the 5377 * conventional lock order during mnt_vnode_next_active iteration. 5378 * 5379 * On entry, the mount vnode list lock is held and the vnode interlock is not. 5380 * The list lock is dropped and reacquired. On success, both locks are held. 5381 * On failure, the mount vnode list lock is held but the vnode interlock is 5382 * not, and the procedure may have yielded. 5383 */ 5384 static bool 5385 mnt_vnode_next_active_relock(struct vnode *mvp, struct mount *mp, 5386 struct vnode *vp) 5387 { 5388 const struct vnode *tmp; 5389 bool held, ret; 5390 5391 VNASSERT(mvp->v_mount == mp && mvp->v_type == VMARKER && 5392 TAILQ_NEXT(mvp, v_actfreelist) != NULL, mvp, 5393 ("%s: bad marker", __func__)); 5394 VNASSERT(vp->v_mount == mp && vp->v_type != VMARKER, vp, 5395 ("%s: inappropriate vnode", __func__)); 5396 ASSERT_VI_UNLOCKED(vp, __func__); 5397 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 5398 5399 ret = false; 5400 5401 TAILQ_REMOVE(&mp->mnt_activevnodelist, mvp, v_actfreelist); 5402 TAILQ_INSERT_BEFORE(vp, mvp, v_actfreelist); 5403 5404 /* 5405 * Use a hold to prevent vp from disappearing while the mount vnode 5406 * list lock is dropped and reacquired. Normally a hold would be 5407 * acquired with vhold(), but that might try to acquire the vnode 5408 * interlock, which would be a LOR with the mount vnode list lock. 5409 */ 5410 held = refcount_acquire_if_not_zero(&vp->v_holdcnt); 5411 mtx_unlock(&mp->mnt_listmtx); 5412 if (!held) 5413 goto abort; 5414 VI_LOCK(vp); 5415 if (!refcount_release_if_not_last(&vp->v_holdcnt)) { 5416 vdropl(vp); 5417 goto abort; 5418 } 5419 mtx_lock(&mp->mnt_listmtx); 5420 5421 /* 5422 * Determine whether the vnode is still the next one after the marker, 5423 * excepting any other markers. If the vnode has not been doomed by 5424 * vgone() then the hold should have ensured that it remained on the 5425 * active list. If it has been doomed but is still on the active list, 5426 * don't abort, but rather skip over it (avoid spinning on doomed 5427 * vnodes). 5428 */ 5429 tmp = mvp; 5430 do { 5431 tmp = TAILQ_NEXT(tmp, v_actfreelist); 5432 } while (tmp != NULL && tmp->v_type == VMARKER); 5433 if (tmp != vp) { 5434 mtx_unlock(&mp->mnt_listmtx); 5435 VI_UNLOCK(vp); 5436 goto abort; 5437 } 5438 5439 ret = true; 5440 goto out; 5441 abort: 5442 maybe_yield(); 5443 mtx_lock(&mp->mnt_listmtx); 5444 out: 5445 if (ret) 5446 ASSERT_VI_LOCKED(vp, __func__); 5447 else 5448 ASSERT_VI_UNLOCKED(vp, __func__); 5449 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 5450 return (ret); 5451 } 5452 5453 static struct vnode * 5454 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 5455 { 5456 struct vnode *vp, *nvp; 5457 5458 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 5459 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5460 restart: 5461 vp = TAILQ_NEXT(*mvp, v_actfreelist); 5462 while (vp != NULL) { 5463 if (vp->v_type == VMARKER) { 5464 vp = TAILQ_NEXT(vp, v_actfreelist); 5465 continue; 5466 } 5467 /* 5468 * Try-lock because this is the wrong lock order. If that does 5469 * not succeed, drop the mount vnode list lock and try to 5470 * reacquire it and the vnode interlock in the right order. 5471 */ 5472 if (!VI_TRYLOCK(vp) && 5473 !mnt_vnode_next_active_relock(*mvp, mp, vp)) 5474 goto restart; 5475 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 5476 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 5477 ("alien vnode on the active list %p %p", vp, mp)); 5478 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 5479 break; 5480 nvp = TAILQ_NEXT(vp, v_actfreelist); 5481 VI_UNLOCK(vp); 5482 vp = nvp; 5483 } 5484 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 5485 5486 /* Check if we are done */ 5487 if (vp == NULL) { 5488 mtx_unlock(&mp->mnt_listmtx); 5489 mnt_vnode_markerfree_active(mvp, mp); 5490 return (NULL); 5491 } 5492 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 5493 mtx_unlock(&mp->mnt_listmtx); 5494 ASSERT_VI_LOCKED(vp, "active iter"); 5495 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 5496 return (vp); 5497 } 5498 5499 struct vnode * 5500 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 5501 { 5502 5503 if (should_yield()) 5504 kern_yield(PRI_USER); 5505 mtx_lock(&mp->mnt_listmtx); 5506 return (mnt_vnode_next_active(mvp, mp)); 5507 } 5508 5509 struct vnode * 5510 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 5511 { 5512 struct vnode *vp; 5513 5514 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 5515 MNT_ILOCK(mp); 5516 MNT_REF(mp); 5517 MNT_IUNLOCK(mp); 5518 (*mvp)->v_type = VMARKER; 5519 (*mvp)->v_mount = mp; 5520 5521 mtx_lock(&mp->mnt_listmtx); 5522 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 5523 if (vp == NULL) { 5524 mtx_unlock(&mp->mnt_listmtx); 5525 mnt_vnode_markerfree_active(mvp, mp); 5526 return (NULL); 5527 } 5528 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 5529 return (mnt_vnode_next_active(mvp, mp)); 5530 } 5531 5532 void 5533 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 5534 { 5535 5536 if (*mvp == NULL) 5537 return; 5538 5539 mtx_lock(&mp->mnt_listmtx); 5540 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 5541 mtx_unlock(&mp->mnt_listmtx); 5542 mnt_vnode_markerfree_active(mvp, mp); 5543 } 5544